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The mechanical behavior of the tin (Sn)–silver (Ag)–copper (Cu) (SAC) lead-free solders is strongly influenced by the isothermal aging due to the evolution of the microstructure and mechanical properties. This study aims to examine the influence of pre-isothermal aging at 100°C on the mechanical behavior of different SACN05 alloys with different silver content including N=1,2,3N=1,\hspace{.25em}2,\hspace{.25em}3 and 4% by applying nonlinear finite element analysis. The mechanical properties, including elastic and inelastic properties, of the SAC systems with various Ag percentages are gathered from the literature and incorporated in thorough thermomechanical simulations. In addition to the unaged solders condition, two aging periods, 6 and 12 months, are studied. The computational results showed that the mechanical response of pre-aged SACN05 solders is significantly influenced by the aging duration and silver content. Specifically, interconnects with higher Ag percentage are shown to be more resistive to aging and expected to have lower thermally induced inelastic deformations, strains, and strain energies. Therefore, better thermal fatigue performance and improved failure resistance is potentially expected. However, the pre-isothermally aged SACN05 solders generally exhibit lower resistance to the accumulations of inelastic strains and strain energies. Thus, it is probable that pre-aged SACN05 solders will demonstrate deterioration in thermal fatigue performance compared to unaged interconnects. Nonetheless, the aged SAC solder systems could be an innovative solution for designing electronic devices regularly exposed to shock and impact loading as the aging process significantly reduces the brittleness of the SnAgCu alloys.

This study aims to assess the effect of the solder joint array layouts, including full and peripheral designs, on the mechanical response and reliability of electronic packages subjected to shock and impact loadings. Linear and nonlinear finite element simulations using the global-local modeling technique are employed to perform the analysis. Several peripheral array configurations are considered and compared to the full array systems. The results showed that, for optimum electronic package designs in terms of reliability and cost, it is highly recommended to use peripheral packages having three or four rows of solder interconnects in electronic systems under shock and impact loadings.

Ajuga orientalis L. (Lamiaceae) is a fragrant herb native to the Eastern Mediterranean region, widely used in traditional healing practices in Jordan and neighboring countries. Despite its extensive use, there is a lack of toxicological studies on its leaf extracts. This study aims to address this gap by evaluating the genotoxic potential of ethanolic and aqueous leaf extracts using a micronucleus (MN) assay on mice DNA, alongside assessing their antioxidant status. The median lethal dose 50% (LD50) was tested in ten groups of sixty male Balb/c mice to determine the acute toxicity of A. orientalis leaf extracts. Four groups of male Balb/c mice (n=6) were used to evaluate micronucleus (MN) formation and total antioxidant capacity for each extract. Each group received daily intraperitoneal injections of one of the following concentrations: 4000, 2000, 1000, and 500 mg/kg over 28 days. Additionally, three control groups were included for comparison purposes. Peripheral blood samples were screened for MN formation, and liver samples were assessed for total antioxidant capacity. Results revealed an LD50 of 4000 mg/kg for both extracts, alongside a significant dose-dependent increase in MN formation and lower antioxidant capacity compared to controls. The findings indicate the genotoxicity of A. orientalis leaf extracts in Balb/c mice, urging caution in human consumption. Further research is warranted to comprehensively assess their safety and toxicity, especially considering their traditional medicinal use. [ABSTRACT FROM AUTHOR]

The alkaloid-rich fraction obtained by fractionation of the crude methanolic extract of the leaves of wild tobacco tree Nicotiana glauca Graham (Solanaceae) was analyzed using UPLC-MS and GC-MS. Anabasine, a piperidine alkaloid, was identified as the major constituent with approximately 60 % (m/m) of the alkaloid-rich fraction. In addition to anabasine, six secondary metabolites were identified using high-resolution UPLC-MS. Anabasine was quantified in the leaves to be 1 mg g−1 dry plant material. The GC-MS analysis revealed five compounds with anabasine as the major component, while nicotine was not detected. Moreover, GC-MS was used for the analysis of the volatile oil that was obtained by hydro-distillation from the leaves of N. glauca. The volatile plant oil was found to be rich in oxygenated sesquiterpenes (e.g., β-bisabolol) and carboxylic acids and esters (e.g., ethyl linoleate and hexadecanoic acid), whereas anabasine was not detected.