Revealing the atomistic mechanisms for the high-temperature mechanical behavior of materials is important for optimizing their properties for service at high-temperatures and their thermomechanical processing. However, due to materials microstructure’s dynamic recovery and the absence of available in situ techniques, the high-temperature deformation behavior and atomistic mechanisms of materials are difficult to evaluate. Here, we report the development of a microelectromechanical systems-based thermomechanical testing apparatus that enables mechanical testing at temperatures reaching 1556 K inside a transmission electron microscope for in situ investigation with atomic-resolution. With this unique technique, we first uncovered that tungsten fractures at 973 K in a ductile manner via a strain-induced multi-step body-centered cubic (BCC)-to-face-centered cubic (FCC) transformation and dislocation activities within the strain-induced FCC phase. Both events reduce the stress concentration at the crack tip and retard crack propagation. Our research provides an approach for timely and atomic-resolved high-temperature mechanical investigation of materials at high-temperatures.

Sertraline and mirtazapine exhibited optimally balanced efficacy, acceptability, and safety for first-line acute treatment of child and adolescent MDD.

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Adjusting the agricultural planting structure is one of the important means to realize agricultural water-saving, especially in arid inland river basin. In this paper, taking Shiyang River Basin as an example, on the basis of determining the crop water production function, a multi-objective optimization model was constructed, which comprehensively considered the maximization of economic benefits, the green water utilization rate and ecological benefits. The optimized planting structure was obtained by using GAMS (General Algebraic Modeling System) model solver. The results showed that: The common features of the three level years after optimization is that the sown area proportion of wheat, tubers, vegetables, fruits and cotton all increased, of which the sown area of fruits increased most by 5.30 × 10 4 ha. However, the sown area proportion of corn and oil-bearing crops decreased, of which the sown area of corn decreased most by 8.90 × 10 4 ha. Comparing of three level years, it is found that the impact of climate change on planting structure adjustment was relatively weak. With the decrease of precipitation, it is suggested to slightly decrease the sown area of wheat but slightly increase the sown area of tubers. The optimization results of planting structure were different in different counties. The average contribution rate of planting structure adjustment to total water-saving was 73.32%, indicating that planting structure adjustment was the key to water-saving. The water consumption of the same crop was different in different counties.