Key Issues in Developing Numerical Models for Artificial Weather Modification

The scientific foundation of artificial weather modification is rneso- and small-scale dynamics and cloud-precipitation microphysics. Artificial weather modification requires the realistic coupling of weather patterns, dynamical pro- cesses, and microphysical processes. Now that numerical models with weather dynamical characteristics have been widely applied to artificial weather modification, several key points that should not be neglected when developing numerical models for artificial weather modification are proposed in this paper, including the dynamical equations, model resolution, cloud-precipitation microphysical processes, numerical computation method, and initial and boundary conditions. Based on several examples, approaches are offered to deal with the problems that exist in these areas.

Stimulated electromagnetic emissions spectrum observed during an X-mode heating experiment at the European Incoherent Scatter Scientific Association

An extraordinary(X-mode)electromagnetic wave,injected into the ionosphere by the ground-based heating facility at Tromsφ,Norway,was utilized to modify the ionosphere on November 6,2017.The high-power high-frequency transmitter facility located at Tromsφ belongs to the European Incoherent Scatter Scientific Association.In the experiment,stimulated electromagnetic emission(SEE)spectra were observed.A narrow continuum occurred under cold-start conditions and showed an overshoot effect lasting several seconds.Cascading peaks occurred on both sides of the heating frequency only in the preconditioned ionosphere and also showed an overshoot effect.These SEE features are probably related to the ponderomotive process in the X-mode heating experiment and are helpful for understanding the physical mechanism that generated them during the X-mode heating experiment.The features observed in the X-mode heating experiments are novel and require further investigation.

A facile,scalable,high stability Lithium metal anode

Li has garnered enormous attention for next-generation Limetal batteries owing to its remarkable theoretical capacity.Unfortunately,as an anode,Li suffers from serious safety issues and fast capacity fading due to the formation of Li dendrites,which hinders the practical application of Li anode.Herein,a LiAlO_(2)-PVDF composite modification layer is fabricated on the surface of Li metal to enhance its stability and electrochemical performance.Benefitting fromthe synergetic effects of high Li+conductivity,high Li+transference number,excellent mechanical properties,superior chemical durability,and compactness of the modification layer,the LiAlO_(2)-PVDF@Li electrode delivers an ultra-long lifespan and a high capacity retention rate in the LiAlO2-PVDF@Li│LiFePO_(4) full cell.The proposed strategy provides a new alternative anode for Li metal batteries with high performance and scalable production.