DEAR EDITOR,Combining location data, species distribution modeling(Max Ent), and major conservation events, we analyzed historical distribution changes in golden snub-nosed monkeys(Rhinopithecus roxellana) in the Qinl...DEAR EDITOR,Combining location data, species distribution modeling(Max Ent), and major conservation events, we analyzed historical distribution changes in golden snub-nosed monkeys(Rhinopithecus roxellana) in the Qinling Mountains of China.展开更多
Abstract The microstructure evolution and composition distribution of as-cast and homogenized 2099 aluminumlithium （Al-Li） alloy were studied by optical microscopy （OM）, differential thermal analysis （DTA）, scan...Abstract The microstructure evolution and composition distribution of as-cast and homogenized 2099 aluminumlithium （Al-Li） alloy were studied by optical microscopy （OM）, differential thermal analysis （DTA）, scanning electron microscopy （SEM）, energy dispersive spectrometry （EDS）, area and line scanning, X-ray diffraction （XRD）, and Vickers microhardness test methods. The results show that severe dendrite exists in the as-cast alloy. Cu, Zn, Mn, and Mg distribute unevenly from the grain boundary to inside. The low-melting point nonequilibrium eutectic phases dis- solve into the matrix during the first-step homogenization, whereas the melting point of residual eutectic phases is elevated. After the second-step homogenization, most of the remaining eutectic phases dissolve into the matrix, except a small amount of A1-Cu-Fe phases. An optimized homogenization process of the 2099 A1-Li alloy is developed （515℃ - 18 h ＋ 525℃ - 16 h）, which shows a good agreement with the homogenization kinetic analysis results.展开更多
基金supported by the National Natural Science Foundation of China (32070457, 32200396, 32000317)Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31020302)+3 种基金Biodiversity Survey and Assessment Project(2019HJ2096001006)Key Cultivation Research Project of Shaanxi Academy of Sciences (2022k-05,2021kp-7,2020k-1,2020K-20)Forestry Reform and Development Foundation of Shaanxi Forestry Bureau (2021)American Society of Primatologists Wild “Saving Primates Where They Live” Partnership Award。
文摘DEAR EDITOR,Combining location data, species distribution modeling(Max Ent), and major conservation events, we analyzed historical distribution changes in golden snub-nosed monkeys(Rhinopithecus roxellana) in the Qinling Mountains of China.
基金financially supported by the National Key Basic Research Development Program of China(No.2012CB619504)
文摘Abstract The microstructure evolution and composition distribution of as-cast and homogenized 2099 aluminumlithium （Al-Li） alloy were studied by optical microscopy （OM）, differential thermal analysis （DTA）, scanning electron microscopy （SEM）, energy dispersive spectrometry （EDS）, area and line scanning, X-ray diffraction （XRD）, and Vickers microhardness test methods. The results show that severe dendrite exists in the as-cast alloy. Cu, Zn, Mn, and Mg distribute unevenly from the grain boundary to inside. The low-melting point nonequilibrium eutectic phases dis- solve into the matrix during the first-step homogenization, whereas the melting point of residual eutectic phases is elevated. After the second-step homogenization, most of the remaining eutectic phases dissolve into the matrix, except a small amount of A1-Cu-Fe phases. An optimized homogenization process of the 2099 A1-Li alloy is developed （515℃ - 18 h ＋ 525℃ - 16 h）, which shows a good agreement with the homogenization kinetic analysis results.
