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This study aims to identify distinct small-scale temporary patterns between the river discharge and suspended sediment load for the main tropical rivers using continuous wavelet transform. Strong annual and irregular semi-annual variabilities, with few quarterly and interdecadal variabilities, are observed in river discharge and sediment load. The wavelet coherence reveals that the strongest in-phase coherence relationships exist between total suspended sediment and streamflow. The methodology for identifying the primary climate factors that integrate the partial wavelet coherence (PWC), multiple wavelet coherence (MWC), and quadruple wavelet coherence (QMWC) techniques is presented. The results show that the El-Nino/Southern Oscillation (ENSO) is the major regulator of streamflow followed by Indian Ocean Dipole (IOD) and Pacific Decadal Oscillation (PDO). The chosen rivers show a statistically significant ($p \le 0.05$p≤0.05) descending trend in sediment load but no significant positive or negative trend in river discharge. This could be due to regional sediment storage and large-scale stream events affecting the sediment transport dynamics. [ABSTRACT FROM AUTHOR]

Fluorescent carbon nanoparticles, also known as carbon quantum dots (CQDs), have piqued the interest of researchers due to their numerous uses in chemical sensing, biomedical imaging, nanotechnology, photovoltaics, LEDs, and hydrogen generation. Aside from their optical brilliance, CQDs have benefits like low toxicity, environmental friendliness, cost‐effectiveness, and ease of manufacture, with adjustable properties via surface passivation and functionalization. This review article goes over CQDs in‐depth, addressing synthesis advances, benefits, limits, various synthesis processes, and prospective hydrogen generation applications. While CQDs have photocatalytic properties, they confront a few challenges, including low quantum yields, spectrum limitations, photostability limitations, limited catalytic activity, scaling difficulties, and environmental issues. Thorough research is required to use CQDs in sustainable hydrogen generation. Despite obstacles, CQD research remains appealing, with transformational promise for a cleaner and more sustainable energy future through controlled synthesis approaches displaying CQDs' many uses. [ABSTRACT FROM AUTHOR]