The microstructures and mechanical properties were systematically studied for the high-strength Al−5Mg_(2)Si−1.5Ni alloy fabricated by laser powder bed fusion(L-PBF).It is found that the introduction of Ni(1.5 wt.%)in...The microstructures and mechanical properties were systematically studied for the high-strength Al−5Mg_(2)Si−1.5Ni alloy fabricated by laser powder bed fusion(L-PBF).It is found that the introduction of Ni(1.5 wt.%)into an Al−5Mg_(2)Si alloy can significantly improve the L-PBF processibility and provide remarkable improvement in mechanical properties.The solidification range of just 85.5 K and the typical Al−Al3Ni eutectics could be obtained in the Ni-modified Al−5Mg_(2)Si samples with a high relative density of 99.8%at the volumetric energy density of 107.4 J/mm^(3).Additionally,the refined hierarchical microstructure was mainly characterized by heterogeneousα-Al matrix grains(14.6μm)that contain the interaction between dislocations and Al−Al3Ni eutectics as well as Mg_(2)Si particles.Through synergetic effects of grain refinement,dislocation strengthening and precipitation strengthening induced by Ni addition,the L-PBFed Al−5Mg_(2)Si−1.5Ni alloy achieved superior mechanical properties,which included the yield strength of(425±15)MPa,the ultimate tensile strength of(541±11)MPa and the elongation of(6.2±0.2)%.展开更多
目的通过meta分析确定膝关节置换术后患者发生恐动症的危险因素。方法计算机检索中国知网、万方医学数据库、维普数据库、中国生物医学数据库、PubMed、Embase、Cochrane Library、CINAHL、Web of Science数据库中关于膝关节置换术后患...目的通过meta分析确定膝关节置换术后患者发生恐动症的危险因素。方法计算机检索中国知网、万方医学数据库、维普数据库、中国生物医学数据库、PubMed、Embase、Cochrane Library、CINAHL、Web of Science数据库中关于膝关节置换术后患者发生恐动症危险因素的文献,按照纳入与排除标准,采用RevMan 5.4软件进行meta分析。结果共纳入10篇文献,包含18个危险因素,meta分析结果显示,疼痛、个人应对方式、自我效能、社会支持、抑郁为膝关节置换术后患者发生恐动症的危险因素(OR=2.74、1.80、1.81、1.83、1.30,P<0.05)。结论膝关节置换术后患者发生恐动症的危险因素较多,护理人员应针对主要危险因素,采用个性化、有针对性的干预措施,防止恐动症的发生。展开更多
基金Financial supports from the National Natural Science Foundation of China (No.52071343)the Leading Innovation and Entrepreneurship Team of Zhejiang Province,China—Automotive Light Alloy Innovation Team (No.2022R01018)are gratefully acknowledged。
文摘The microstructures and mechanical properties were systematically studied for the high-strength Al−5Mg_(2)Si−1.5Ni alloy fabricated by laser powder bed fusion(L-PBF).It is found that the introduction of Ni(1.5 wt.%)into an Al−5Mg_(2)Si alloy can significantly improve the L-PBF processibility and provide remarkable improvement in mechanical properties.The solidification range of just 85.5 K and the typical Al−Al3Ni eutectics could be obtained in the Ni-modified Al−5Mg_(2)Si samples with a high relative density of 99.8%at the volumetric energy density of 107.4 J/mm^(3).Additionally,the refined hierarchical microstructure was mainly characterized by heterogeneousα-Al matrix grains(14.6μm)that contain the interaction between dislocations and Al−Al3Ni eutectics as well as Mg_(2)Si particles.Through synergetic effects of grain refinement,dislocation strengthening and precipitation strengthening induced by Ni addition,the L-PBFed Al−5Mg_(2)Si−1.5Ni alloy achieved superior mechanical properties,which included the yield strength of(425±15)MPa,the ultimate tensile strength of(541±11)MPa and the elongation of(6.2±0.2)%.
文摘目的通过meta分析确定膝关节置换术后患者发生恐动症的危险因素。方法计算机检索中国知网、万方医学数据库、维普数据库、中国生物医学数据库、PubMed、Embase、Cochrane Library、CINAHL、Web of Science数据库中关于膝关节置换术后患者发生恐动症危险因素的文献,按照纳入与排除标准,采用RevMan 5.4软件进行meta分析。结果共纳入10篇文献,包含18个危险因素,meta分析结果显示,疼痛、个人应对方式、自我效能、社会支持、抑郁为膝关节置换术后患者发生恐动症的危险因素(OR=2.74、1.80、1.81、1.83、1.30,P<0.05)。结论膝关节置换术后患者发生恐动症的危险因素较多,护理人员应针对主要危险因素,采用个性化、有针对性的干预措施,防止恐动症的发生。
