Numerical three‐dimensional magnetohydrodynamic models are capable of predicting large‐scale solar wind structures at Earth, provided that appropriate time‐dependent boundary conditions are specified near the Sun. Since knowledge of such conditions is at present insufficient to directly drive the models, various approximations are used. In this paper, we introduce the main features and approximations of a numerical model where (1) the ambient solar wind is derived from coronal models utilizing photospheric magnetic field observations and (2) transient disturbances are derived from geometrical and kinematic fitting of coronagraph observations of coronal mass ejections (CMEs). We have chosen the well‐defined halo‐CME event of 12 May 1997 as our initial event because it is characterized by a relatively quiet solar and interplanetary background into which the ejecta was launched. The numerical simulation has enabled us to predict the arrival of the shock and ejecta and provided us with a global picture of transient disturbance interacting with a moderately fast solar wind stream.

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The electrochemical method of combining N2 and H2O to produce ammonia (i.e., the electrochemical nitrogen reduction reaction [E‐NRR]) continues to draw attention as it is both environmentally friendly and well suited for a progressively distributed farm economy. Despite the multitude of recent works on the E‐NRR, further progress in this field faces a bottleneck. On the one hand, despite the extensive exploration and trial‐and‐error evaluation of E‐NRR catalysts, no study has stood out to become the stage protagonist. On the other hand, the current level of ammonia production (microgram‐scale) is an almost insurmountable obstacle for its qualitative and quantitative determination, hindering the discrimination between true activity and contamination. Herein i) the popular theory and mechanism of the NRR are introduced; ii) a comprehensive summary of the recent progress in the field of the E‐NRR and related catalysts is provided; iii) the operational procedures of the E‐NRR are addressed, including the acquisition of key metrics, the challenges faced, and the most suitable solutions; iv) the guiding principles and standardized recommendations for the E‐NRR are emphasized and future research directions and prospects are provided.

WS2 nanodots were prepared by liquid-phase exfoliation of bulk WS2 crystals in surfactant aqueous solution with the aid of ultrasonication. Their behaviors on catalyzing hydrogen evolution reaction (HER) were investigated after drop-casting them onto a glass carbon electrode. On the basis of the optical and electron characterizations, the nanodots were identified with a high concentration of octahedral phase of WS2 that showed better catalysis properties than the hexagonal WS2. From the polarization curve, the Tafel slope was estimated to be 51 mV per decade and the onset potential was 90 mV, indicating good catalytic performance of such nanodots. Our results suggest that surfactant-mediated exfoliation is an environmentally benign method to synthesize WS2 nanodots for improved catalyzing HER.