Herbicide resistance has become one of the foremost problems in crop production worldwide. New herbicides are required to manage weeds that have evolved resistance to the existing herbicides. However, relatively few herbicides with new modes of action (MOAs) have been discovered in the past two decades. Therefore, the discovery of new herbicides (i.e., new chemical classes or MOAs) remains a primary but ongoing strategy to overcome herbicide resistance and ensure crop production. In this mini‐review, starting with the inherent characteristics of the target proteins and the inhibitor structures, we propose two strategies for the rational design of new herbicides and one computational method for the risk evaluation of target mutation‐conferred herbicide resistance. The information presented here may improve the utilization of known targets and inspire the discovery of herbicides with new targets. We believe that these strategies may trigger the sustainable development of herbicides in the future. © 2021 Society of Chemical Industry

Electret melt-blown nonwovens are widely used for air purification due to their low pressure drop and high filtration efficiency. However, the charge stability could be affected by the ambient temperature and humidity, reducing the filtration efficiency, resulting in the electret melt blown filter not providing effective protection. Herein, we used corona charge to prepare electret melt-blown nonwovens and systematically studied the effects of different temperature and humidity on the structure, morphology, filtration performance, and surface potential within 24 h. The effect of treatment temperature and humidity on pressure drop was minimal because the fiber morphology and web structure of melt-blown nonwovens were not damaged. When the treatment temperature was lower than 70 °C, the effect on the filtration efficiency of the sample was small, but when the temperature increased to 90 or 110 °C, the filtration efficiency decreased significantly with the increase of the treatment time, and the surface potential also declined similarly. In conclusion, high temperatures will lead to charge escape and reduce the electrostatic adsorption effect. Furthermore, at the same temperature, increasing relative humidity can accelerate the charge release and make the filtration efficiency drop more. After the sample was treated at 110 °C and 90% relative humidity for 24 h, the filtration efficiency decreased from 95.49% to 38.16% at a flow rate of 14.16 cm s−1, and the surface potential dropped to the lowest value of −1.01 kV. This result shows that all links of electret melt-blown filter material from raw material to final use should be avoided in high temperature and high humidity conditions to ensure the protection effect.

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Laser shock peening (LSP) is an innovative surface treatment process with the potential to change surface microstructure and improve mechanical properties of additively manufactured (AM) parts. In this paper, the influences of LSP on the microstructure and properties of Ti–6Al–4V (Ti64) titanium alloy fabricated via selective laser melting (SLM), as an attractive AM method, were investigated. The microstructural evolution, residual stress distribution and mechanical properties of SLM-built Ti64 samples were characterized before and after LSP. Results show that the SLM sample was composed of single hcp α’ phase, which deviates from equilibrium microstructure at room temperature: α + β phases. The LSP significantly refines the grains of α’ phase and produces compressive residual stress (CRS) of maximum magnitude up to −180 MPa with a depth of 250 μm. Grain refinement of α’ phase is attributed to the complex interaction of dislocations and the intersection of deformation twinning subjected to LSP treatment. The main mechanism of strength and micro-hardness enhancement via LSP is ascribed to the effects of CRS and α’ phase grain refinement.

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