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Classical J2 plasticity theory is the most popular continuum plasticity model. However, this plasticity theory is inapplicable for some metals due to the tension/compression asymmetry behavior. According to our previous study, the tension and compression mechanical response of laser-solid-formed Ti–6Al–4V alloy was significantly different in not only yield stress but also work hardening rate. In this study, effects of temperature and strain rate on the tension/compression asymmetry behavior of laser-solid-formed Ti-6Al-4V alloy were analyzed. Through mechanism discussion, different activations of slip systems and deformation twinning were considered to be the main causes of the tension/compression asymmetry. Finally, an improved constitutive model was developed, considering the synergistic effects of temperature, strain rate, and stress state on the plastic behavior of laser-solid-formed Ti–6Al–4V alloy. The calibrated model can accurately describe the temperature and strain rate dependences of the tension/compression asymmetry behavior. To verify the applicability of the developed constitutive model at different stress state, dynamic shear tests and finite element simulations were conducted at different temperatures. The improved constitutive model was shown to be able to predict the plastic behavior of laser-solid-formed Ti–6Al–4V alloy at different stress states over a wide range of temperatures and strain rates. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are promising nanoporous materials with diverse applications. Traditional material discovery based on intensive manual experiments has certain limitations on efficiency and effectiveness when faced with nearly infinite material space. The current situation offers an opportunity for high-throughput (HT) and machine learning (ML) approaches, including computational and experimental methods, as they have greatly improved the efficiency of MOF screening and discovery and have the capacity to deal with the enormous growth of data. In this review, we discuss the research progress in HT computation and experiments and their effect on MOF screening and discovery. We also highlight how ML-based approaches and the integration of HT methods with ML algorithms accelerate MOF design. In addition, we provide our insights on the future capability of data-driven techniques for MOF discovery, despite facing some knowledge gaps as an obstacle. [ABSTRACT FROM AUTHOR]

A new diarylethene derivative 1O decorated with a salicylaldehyde hydrazine moiety was designed and synthesized successfully, and its structure was confirmed by NMR. Diarylethene 1O showed eminent photochromism and high selectivity and sensitivity for Al3+ with turn-on fluorescent performance. As the concentration of Al3+ in 1O solution increased, the color of solution remarkably changed from dark to bright green with 313-fold fluorescent emission intensity enhancement. The 1:1 combination stoichiometry between 1O and Al3+ was verified by Job's plot and MS analysis. The association constant between 1O and Al3+ was 3.9 × 102 mol−1 L, and the limit of detection toward Al3+ was 7.98 × 10–9 mol L−1. Meanwhile, the probe can be utilized in practical water and logic circuits. [ABSTRACT FROM AUTHOR]