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Effects of Sn and Gd additions on the (β1 + β3) field in the Cu-11%Al-10%Mn alloy were studied by in situ X-ray diffraction, differential scanning calorimetry, non-isothermal kinetics, and magnetization measurements as a function of the temperature. The microstructures were investigated using optical microscopy and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. The results showed that the β 3 Cu 2 AlMn + β 1 Cu 3 Al → β 3 Cu 2 AlMn reaction is strongly dependent on the heating and cooling rates. The Sn addition to the Cu-11%Al-10%Mn alloy stabilizes the ferromagnetic β3 phase. In the Sn-containing alloy, the miscibility gap transition is followed by the martensitic transformation at about 560 K. Both Sn and Gd additions have extended the stability field of the ferromagnetic β3 phase. Nonetheless, the formation of Cu5Gd precipitates slows the miscibility gap transition on heating, which may be associated with the reduction of the ferromagnetic phase amount at room temperature in the Cu11%Al10%Mn3%Gd alloy. [ABSTRACT FROM AUTHOR]

The Cape petrel (Daption capense) has circumpolar distribution and potential to be used as sentinels of trace elements levels in the Antarctic environment. This study measured trace elements in carcass feathers (n = 30) of this yet under-studied Procellariiform species, in King George Island, Antarctica. This non-invasive sampling method was useful for quantifying mercury (Hg), cadmium (Cd), selenium (Se), and to perform the sex identification of birds. There were no significant differences between males and females for Hg (mean ± SD, 973 ± 930 ng g−1; 977 ± 570 ng g−1) and Se (3919 ± 637 ng g−1; 3782 ± 799 ng g−1), levels but males had significantly lower Cd levels than females (101 ± 76 ng g−1; 293 ± 251 ng g−1), respectively. Hg concentration in D. capense is lower than other Procellariiformes which indicate interspecific variations that may be related to their proximity to pollution sources. The reason for males having significantly lower Cd levels than females is unknown. This opportunistic and non-invasive sampling strategy can be useful in the environmental monitoring of the trace elements in polar environments. [ABSTRACT FROM AUTHOR]

In this work, the effects of 3Gd and 3Sn additions on thermal behavior of the as-cast Cu–11Al–10Mn alloy (compositions in mass%) have been studied using differential thermal analysis, differential scanning calorimetry, scanning electron microscopy, optical microscopy, magnetization measurements with applied field and X-ray diffractometry. The results have shown that the melting point of the as-cast Cu–11Al–10Mn alloy is modified with addition of Sn. As-cast samples of the Cu–11Al, Cu–11Al–3Gd and Cu–11Al–3Sn alloys were solidified with microstructures and phase relationships near those found in as-quenched samples. Magnetization curves with applied field indicated that the presence of Sn increases the saturation magnetization, whereas Gd decreases the value of this property, as compared with as-cast Cu–11Al–10Mn alloy. This behavior suggests a higher amount of ferromagnetic Cu2AlMn ( β 3 ) phase in the as-cast Cu–11Al–10Mn–3Sn alloy, showing that the Sn modifies the phases equilibrium in the as-cast Cu–11Al–10Mn alloy. [ABSTRACT FROM AUTHOR]

In this work, the effects of Ag addition on phase transitions, microstructure and solder/copper interfaces of Sn99.1−xCu0.9Agx alloys were studied using differential scanning calorimetry, X-ray diffractometry, electron scanning microscopy and energy-dispersive X-ray spectroscopy. The results showed that the addition of Ag to the Sn99.1Cu0.9 alloy changes the thermal behavior of the melting and solidification points of studied alloys. The presence of silver also induced the formation of the Ag3Sn phase and decreased the amount of the Cu6Sn5 compound. [ABSTRACT FROM AUTHOR]