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. The earthquake records were divided into different groups according to pulse period and the displacement response spectra under pulse-type ground motions was solved by using Matlab. The features of the displacement response spectra were studied by means of normalizing and averaging, displacement design spectra using pulse period as characteristic period was established by using piecewise linear......
in the incubation experiment with a period of 35 d. The results indicate that all the tested Cr(Ⅵ) concentrations significantly inhibit dehydrogenase activity by over 70% after 35 d. The activity of alkaline... physical and chemical properties are presented in Table 1. The sampled soil was air-dried and then sieved through a 2-mm mesh prior to use. 2.2 Incubation experiment 250 g of the sieved soil (dry......
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: Polyimide-supported and silicon-supported Cu-Cr nanostructured metallic multilayers with constant modulation ratio (η) and constant modulation period (λ) were respectively synthesized by means... effect at a critical modulation period λc (≈25 nm) or a critical modulation ratio ηc ( ≈1). Key words: nanostructured metallic multilayers; strength; hardness; modulation period; modulation ratio 由两种或......
热变形对高铌低碳钢奥氏体→铁素体等温转变影响研究曹建春1,周晓龙1,何寒1,陈文1,刘清友2,雍岐龙2(1.云南省昆明市昆明理工大学材料科学与工程学院2.钢铁研究总院 结构材料研究所,北京 100081)摘 要:针对热变形对铌质量分数为0.17%的低碳钢的奥氏体→铁素体等温相变动力学的影响,通过热模拟试验,分析未变形,875℃变形20%和30%条件下奥氏体向铁素体700℃等温转变的动力学,讨论了热变形和铌对奥氏体→铁素体等温相变的影响机制.研究结果表明:热变形主要通过缩短相变孕育期来加速奥氏体→铁素体等温相变;......
, the lamellar 14H-type long period stacking ordered (LPSO) structure within matrix, and β-[(Mg,Zn)3Gd] phase. However, most of the β-phase transforms to X-phase with 14H-type LPSO structure after... with LPSO structure in the alloy. Key words: Mg-Gd-Zn-Zr alloy; long period stacking ordered (LPSO) structure; microstructure; friction; wear 1 Introduction Magnesium alloys have been attractive......
℃,and the incubation period at the nose temperature is about 0.87 s.When 7B50 alloy was isothermal treated at 180-400℃ after solid solution treatment(470℃ for 1 h followed by 483℃ for 2 h),the exponent(n......
austenite,resulting in the transformation region of bainite and perlite of 0.07 RE steel shifting to the bottom right and prolonging the incubation period compared with that of ORE steel.关键词:......
with the stable potential of -1.455 V (vs SHE), corrosion current density of 0.063 mA/cm2 and average rate of hydrogen evolution of 0.8 mL/(cm2·h). There is an incubation period to the corrosion onset......