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The microstructure of Mg-12Y-1Al alloy with solution treatment and aging treatment was studied by optical microscope, X-ray diffraction and scanning electron microscope. The mechanical properties of the alloy before and after heat treatment at room temperature and 200 ℃ were analyzed by tensile test, and the corrosion resistance of the alloy before and after heat treatment was tested by electrochemical methods. The results show that the as-cast microstructure of Mg-12Y-1Al alloy is composed of α-Mg matrix, Mg24Y5 phase and Al2Y phase. Mg-12Y-1Al alloy has excellent high-temperature thermal stability. After solution treatment at 520 ℃ for 16 h(T4), the grain size does not increase, and new long period stacking ordered(LPSO) phase forms; the subsequent aging treatment at 225 ℃ for 30 h(T6) has little effect on the microstructure. Compared with the properties at room temperature, the ultimate tensile strength of T4 alloy at 200 ℃ does not decrease, but the elongation increases from 1.3% to 12.5%. Moreover, the corrosion resistance of Mg-12Y-1Al alloy is improved after solution and aging treatment, and the corrosion current density decreases from 2.799×10-5 A/cm2 to 1.551×10-5 A/cm2.

Objective To analyze the incidence of birth defects during whole pregnancy in military children in cold region, and explore its epidemiological characteristics and influencing factors. Methods A case-control trial was conducted on 1 883 military fetuses (from 12 weeks of gestation to 7 d after birth, including live birth, stillbirth and odinopoeia) delivered in our hospital from January 2017 to December 2020, and they were selected for birth defect detection at hospital level. A total of 2 198 military fetuses (from 12 weeks of gestation, including live births, stillbirths, odinopoeia and children) delivered in Shenyang and its surrounding areas from January 2017 to December 2020 were selected for birth defect detection at population level. Data were collected by filling the Birth Defects Epidemiological Questionnaire for Military Children in Cold Region. The incidence, sequence and influencing factors of birth defects during whole pregnancy under hospital surveillance and population surveillance were analyzed. Results ① From 2017 to 2020, the incidence of birth defects during whole pregnancy was 175.25/10 000 (33/1 883) in military children in cold region under hospital surveillance, was 175.47/10 000 (480/27 355) in local people in cold region under hospital surveillance, and was 218.38/10 000 (48/2 198) in military children in cold region under population surveillance. ② The top 3 birth defects in hospital surveillance and population surveillance were external ear malformation, syndactyly and/or polydactyly, and congenital heart disease. ③ Lower education level and proportion of milk intake ≥500 mL/week were observed in the mothers delivering infants with birth defects than those with normal neonates (P < 0.05). Higher birth defects were also seen among one or both parents exposure to radar, radio wave and high electromagnetic radiation than the parents in normal environment (P < 0.05). Multivariate logistic regression analysis showed that maternal education level of junior college or below (OR=2.218), one or both parents with radar exposure (OR=2.179), radio exposure (OR=3.446) and high electromagnetic radiation exposure (OR=2.687) were risk factors for birth defects, and maternal milk intake ≥500 mL/week (OR=0.546) was a protective factor. Conclusion The incidence of birth defects in military children in cold region is basically similar to that in local people. The top 3 birth defects are external ear malformation, syndactyly and/or polydactyly, and congenital heart disease. Low maternal education level, parents' exposure to radar, radio waves and high electromagnetic radiation are risk factors for birth defects in military children in cold region.

The traditional preparation process of superhydrophobic surfaces(SHS) is complicated and the mechanical stability of SHS is less than satisfactory in most cases, which seriously restricts the practical application. The "binder+nanoparticles" strategy was used to prepare a nonfluorinated, durable and stable superhydrophobic epoxy composite coating on magnesium alloy. The contact angle test results show that the maximum contact angle of the composite coating is 160.2°, and the contact angle is still as high as 103° even after 30 days of soaking in 3.5%(mass fraction) NaCl solution; EIS results indicate that the |Z|0.01 Hz of the composite coating is still above 109 Ω·cm2 even after five accelerated aging cycles, demonstrating excellent resistance to salt fog and anticorrosion performance; Friction and wear test results reveal that the |Z|0.01 Hz of the composite coating is as high as 1.84×109 Ω·cm2 after mechanical friction under 19.6 N load for 8 h. Due to the excellent blocking barrier of "air cushion", the composite coating can provide efficient and durable corrosion protection for magnesium alloy and the "adhesive+nanoparticles" strategy provides a new direction for the preparation of superhydrophobic coating.

VW63Z magnesium alloy, known for its high strength-to-weight ratio and excellent mechanical properties, is a promising candidate for applications in the automotive industries. Among the anti-corrosion technologies for VW63Z alloys, organic electrophoretic coatings have gained significant attention due to their ability to provide a uniform and controlled coating thickness, high coating adhesion, and excellent corrosion protection properties. In this work, to investigate the aging behaviors of an organic electrophoretic coating for magnesium alloys, water absorption kinetics curves of the coatings after immersion in 3.5 wt.% NaCl at 20 °C and 40 °C were measured, and parameters such as the saturated water absorption and saturation time of the free film coatings were fitted to determine the densification evolution of the organic coatings. A tensile test was used to test the tensile strength of the organic coating during service to determine the evolution of the strength and toughness of the organic coating. The evolution of wet adhesion of organic coatings with service time was tested by ASTM D4541-02. The impedance spectra of the organic coatings under the above conditions were detected by EIS, and finally, the failure behavior of the organic coatings under immersion was analyzed. [ABSTRACT FROM AUTHOR]