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This study examines the differences related to microphysical properties of ice in thunderstorms over the Amazon and Congo Basin using the Precipitation Feature (PF) data sets derived from passive microwave and radar observations from the Tropical Rainfall Measuring Mission and Global Precipitation Mission Core Satellites. Analysis reveals that Amazon thunderstorms are likely composed of ice crystals smaller but more numerous than those in the Congo Basin, resulting in half as many flashes per PF on average in the Amazon, for similar Ice Water Content (IWC) or Area of 30 dBZ at −10°C (Acharge). The increase of the flash count following an increase of the IWC (Acharge) is only 72% (61%) as effective in the Amazon as it would be in the Congo Basin area. PFs with similar 30 dBZ radar echo top heights exhibit lower Brightness Temperatures (TBs) in the 85/89, 165, and 183 GHz frequencies over the Amazon, indicating more numerous smaller ice particles compared to those over the Congo Basin, which tend to show colder TBs at 37 GHz, possibly due to more numerous large graupel or hail particles. Comparisons of TBs in PFs with similar 30 dBZ echo top temperature between the Amazon and 3 × 3º global grids show that the median TB in Amazon is higher than that in most oceanic areas but is comparable to areas having high oceanic lightning activity (e.g., South Pacific Convergence Zone). It suggests that systems in the Amazon have similarities with maritime precipitation systems, yet with distinct characteristics indicative of land systems. Plain Language Summary: A comparison is made between Amazon (AM) and Congo Basin (CB) thunderstorms with similar reflectivity values seen by either TRMM or GPM, versus other variables that can help us understand the ice microphysics of these storms (IWC, area of 30 dBZ at −10C, Flash count, TBs). The radar reflectivity being driven by number and size (to the sixth power) of hydrometeors, the hypothesis is that for two storms with a same reflectivity value, one in AM and one in CB, the reflectivity value measured is driven by a higher concentration of large ice particles in CB (i.e., driven by size), while it is driven by a higher concentration of smaller ice particles in AM (i.e., driven by number). We quantify the lightning count difference between the two areas as a function of the amount of ice in the thunderstorm. It shows that AM produces significantly less lightning than CB on average for a similar ice content. Radiometers from TRMM and GPM are then used to compare the median TBs observed in the Amazon with the rest of the globe, to emphasize once again that AM is producing systems that are neither of land nor oceanic nature, but somewhere in the middle. Key Points: Amazonian systems are principally composed of smaller and more numerous ice crystalsIncreasing the Ice Water Content (IWC) and/or core size of thunderstorms in the Amazon demonstrates lower effectiveness in boosting lightning activityAmazonian systems present brightness temperatures unlike land or oceans but similar to oceanic regions with greater lightning activity [ABSTRACT FROM AUTHOR]

A series of flower-like Fe0-Fe3O4@MoS2 composite catalysts were successfully synthesized by reducing Fe0 on the surface of Fe3O4 hollow spheres and coating with MoS2 to activate peroxomonosulfate (PMS) for tetracycline hydrochloride (TC) degradation. Adding Fe0 increased the Fe2+ content, and the surface-coated 1T/2H mixed phase MoS2 enhanced the redox cycle of Fe (II)/Fe (III) and the reactivity of the heterogeneous system. Subsequently, the quenching experiments showed that radical and non-radical pathways were present in the Fe0-Fe3O4@MoS2/PMS system, and O2−· and 1O2 were dominant in the degradation. Moreover, the experimental results demonstrated that Fe0-Fe3O4@MoS2 exhibited excellent degradation efficiency (96.81%) and anti-interference capability against anions and humic acid. On this basis, the reaction mechanism was analyzed, and three possible degradation pathways were proposed by LC–MS to detect intermediates of TC. [ABSTRACT FROM AUTHOR]