Gd50Al3oCo20 wires show excellent magnetocaloric properties and high heat exchange rate due to the microsize. The Weibull and lognormal methods were used for systematically analyzing its mechanical properties for matc...Gd50Al3oCo20 wires show excellent magnetocaloric properties and high heat exchange rate due to the microsize. The Weibull and lognormal methods were used for systematically analyzing its mechanical properties for matching the design requirements in cooling system. The wire exhibits average fracture strength of-969.5 MPa and typical fracture behavior of amorphous character. Moreover, the distributions of stresses for tensile strains at 10 values are estimated by probability plot and Chi-square goodness-of-fit test. The random stresses were best fitted by lognormal probability distribution for most studied cases; however, fracture strength was best fitted by Weibull probability distribution. It is interesting to note that the mean and standard deviation of the stresses （to reach specific tensile strain） increase as the tensile strain grows, accompanied by the coefficients of variation of stresses which decrease smoothly. It is concluded that the inhomogeneity of material does cause the scatter of stresses growth, and the scatter could be considerably large.展开更多
探讨了运用Al-Ferron逐时络合比色分光光度法进行Al30分析的适用性.与传统ferron比色法属于操作性的定义不同,该方法对Al-Ferron逐时络合比色的时间扫描数据进行非线性拟合,并假定3种动力学可测形态:一种是瞬时完成的0级反应的铝单体;...探讨了运用Al-Ferron逐时络合比色分光光度法进行Al30分析的适用性.与传统ferron比色法属于操作性的定义不同,该方法对Al-Ferron逐时络合比色的时间扫描数据进行非线性拟合,并假定3种动力学可测形态:一种是瞬时完成的0级反应的铝单体;另两种是一级反应的待定形态.以拟合得到的特征k值和吸光度,作为定性和定量的依据.结果表明:通过优化拟合改进的ferron比色法,可以获得Al30的特征k值,其值在15 mL ferron比色体系中为7×10-5数量级;Al30用ferron比色法的定量分析结果与27Al NMR鉴定结果基本一致,可用以定量分析Al30.该方法既可替代昂贵的27Al NMR鉴定,又能弥补传统ferron比色法定性模糊的不足.展开更多
基金The authors are thankful for the supports from the Key National Natural Science Foundation of China （No. U1533202）, the Shandong Independent Innovation and Achievements Transformation Fund （No. 2014CGZHl101）, the Civil Aviation Administration of China （No. MHRD20150104）, National Sciencetechnology Support Plan Project ＂the application paradigm of full lifecycle information closed-loop management for construction machinery＂ （No. 2015BAF32B01-4） and National Natural Science Foundation of China （Nos. 51775132, 51671071 and 51371067）.
文摘Gd50Al3oCo20 wires show excellent magnetocaloric properties and high heat exchange rate due to the microsize. The Weibull and lognormal methods were used for systematically analyzing its mechanical properties for matching the design requirements in cooling system. The wire exhibits average fracture strength of-969.5 MPa and typical fracture behavior of amorphous character. Moreover, the distributions of stresses for tensile strains at 10 values are estimated by probability plot and Chi-square goodness-of-fit test. The random stresses were best fitted by lognormal probability distribution for most studied cases; however, fracture strength was best fitted by Weibull probability distribution. It is interesting to note that the mean and standard deviation of the stresses （to reach specific tensile strain） increase as the tensile strain grows, accompanied by the coefficients of variation of stresses which decrease smoothly. It is concluded that the inhomogeneity of material does cause the scatter of stresses growth, and the scatter could be considerably large.
文摘探讨了运用Al-Ferron逐时络合比色分光光度法进行Al30分析的适用性.与传统ferron比色法属于操作性的定义不同,该方法对Al-Ferron逐时络合比色的时间扫描数据进行非线性拟合,并假定3种动力学可测形态:一种是瞬时完成的0级反应的铝单体;另两种是一级反应的待定形态.以拟合得到的特征k值和吸光度,作为定性和定量的依据.结果表明:通过优化拟合改进的ferron比色法,可以获得Al30的特征k值,其值在15 mL ferron比色体系中为7×10-5数量级;Al30用ferron比色法的定量分析结果与27Al NMR鉴定结果基本一致,可用以定量分析Al30.该方法既可替代昂贵的27Al NMR鉴定,又能弥补传统ferron比色法定性模糊的不足.
