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This paper aims to investigate the transformations during aging at 200°C for different periods on microstructure and mechanical properties of high-temperature Zn-4Al-3Mg solders.

The solder was melted in a resistance furnace, and different cooling rates were obtained by changing the cooling medium. Subsequently, all the specimens were aged at 200°C for 20 h and 50 h. A scanning electron microscope equipped with an energy dispersive X-ray detector and X-ray diffraction were used for the observation of microstructures and the determination of phase composition. Tensile tests and Rockwell hardness tests were also performed.

After aging, Zn atoms precipitated from the supersaturated α-Al and the (α-Al + η-Zn)_eutectoid phase with the original fine lamellar structure coarsened and spheroidized to minimize the system energy. Among these solders, the furnace-cooled alloys exhibited the highest thermal stability, largely retaining their original morphology after aging, whereas the collapse and spheroidization of the η-Zn phase and the coarsening of the η-Zn dendrites took place in the air-cooled and water-cooled samples, respectively. Furthermore, a decrease in tensile strength during aging was attributed to the thermal softening effect. The variation of macro-hardness was mainly associated with the microstructural alterations in terms of quantity, morphology and distribution of soft η-Zn phase and hard intermetallic compounds induced by the aging treatment.

The structural stability of eutectic Zn-4Al-3Mg solders solidified at different cooling rates and the effect of aging on mechanical properties were investigated.

The social safety net of health care insurance is rapidly expanding in rural China. New Rural Cooperative Medical System (NRCMS) programs proliferated between the national decree of 2002 and 2008, moving from a situation where less than 10 per cent of the rural population had access to health insurance to one where over 80 per cent had the opportunity to participate in these programs. The purpose of this paper is to investigate how NRCMS affects equity goals in access to health care and explore the gender‐specific determinants for farmers to participate in NRCMS and use health care services.

Empirical analysis, by using the national rural socio‐economic survey data collected by the Centre for Chinese Agricultural Policy, Chinese Academy of Sciences in 2005. Based on Andersen's access to medical care model, the probit model for regression was used. All analyses are conducted with Stata 9.0 software.

Gender was found to have significant effects on both NRCMS participation and health care use. Age, education, deductible level and ceiling limits of reimbursement had positive effects on both NRCMS participation and health care use. The narrow coverage with high co‐payment compensation system asserted significant deterrence effects on equity access to health care. This is only a first step toward building an adequate health safety net for all rural residents, there is still a long way to go.

Using the national household survey data, this study is one of few studies focusing on the interplay between gender and the distinct determinants of access to health care under the ongoing NRCMS. The relevant findings have important implications for further policy design.