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Mineral dust plays an important role in Earth's climate system, yet it is difficult to identify dust imprints in paleofluvial sediments, especially on orbital timescales. Here, we present high‐resolution authigenic carbonate Ca–Mg–Sr compositions in a fluvial sequence under the transport pathway of Asian dust. The Mg/Ca, Sr/Ca, and Mg/Sr ratios exhibit distinct transitions in both secular trends and orbital cycles at ∼8 Ma. Before ∼8 Ma, given similar Mg and Sr partitioning behaviors during carbonate formation, hydroclimate changes yielded strong orbital signals in the Sr/Ca and Mg/Ca ratios but no detectable signals in the Mg/Sr ratios. After ∼8 Ma, given the strengthened input of Mg‐rich dust during cold‒dry periods, the Mg/Sr and Mg/Ca ratios clearly exhibited orbital signals, but the Sr/Ca ratio did not. Such transitions in carbonate composition corroborate the dust‐induced changes in fluvial hydrochemistry, offering an innovative methodology for detecting orbital dust cycles in paleofluvial systems. Plain Language Summary: A set of criteria, that is, transport and sedimentation dynamics, the surface morphology of quartz grains and provenance indices, were employed to recognize eolian deposits in past fluvial sediments. However, distinguishing eolian dust at orbital scales poses a challenge, as high‐resolution records that meet these criteria are difficult to reconstruct. Here, we present high‐resolution records of authigenic carbonate compositions from Neogene fluvial sediments in the Linxia Basin, a key downwind catchment area for Asian dust. The carbonate elemental compositions, in conjunction with sedimentary Sr‒Nd isotopes, exhibit a long‐term two‐stage evolution marked by a pivotal shift at ∼8 Ma. This transition is most likely attributed to an increase in Asian dust deposition since that time. On orbital timescales, the periodic fluctuations in extrabasinal dust flux, characterized by Mg‐rich but Sr‐poor components (mostly dolomite), have led to pronounced alterations in the orbital patterns of carbonate Ca‐Mg‐Sr compositions since ∼8 Ma. Our findings indicate that carbonate Ca‐Mg‐Sr compositions can offer a straightforward and innovative approach for pinpointing eolian dust activity on orbital timescales when extrabasinal dust can be appropriately distinguished. Key Points: A close examination of carbonate compositions offers a new method for identifying orbital dust cycles within continental fluvial systemsThe authigenic carbonate composition in a fluvial sequence in NE Tibet shows a distinct orbital transition at ∼8 MaMg‐rich dust markedly altered the river chemistry during the cold/arid stages, with a less pronounced effect during the warm/humid stages [ABSTRACT FROM AUTHOR]

Non‐noble Ni−Cu alloys serve as an alternative catalytic material for noble metal‐based catalysts that could be applied in the efficient conversion of levulinic acid (LA) into the high value γ‐valerolactone (GVL). However, maintaining the catalytic stability for Ni−Cu nanoparticles in the LA hydrogenation process remains a substantial challenge, Herein, this problem is solved by constructing carbon‐protected catalytic sites within carbon layer‐coated Ni−Cu nanoalloy composite via pyrolysis of NiCux(OH)/glucose precursor. The optimized NiCu0.68@C catalyst exhibits excellent stability and selectivity to GVL (>99 %) in the hydrogenation of LA reaction. Various characterization indicates that the enhancement in stability originates from the protective effect of the carbon layer, which prevents the metal leaching, oxidation and aggregation of Ni−Cu nanoparticles during the reaction process. This work greatly advances non‐noble metal‐catalyzed conversion of LA to GVL and helps the rational design of bimetallic catalysts. [ABSTRACT FROM AUTHOR]

Catalytic olefin metathesis represents a vital reaction in the chemical industry, as it provides a feasible route for the interconversion of olefins. However, traditional supported catalysts usually suffer from low activity due to sluggish kinetics for the formation of catalytically active metal‐carbene species. This work tackles this issue by taking phosphoric acid as a promoter and constructing a Brønsted acidic site to cooperate with the MoOx sites, thus facilitating the formation of Mo‐carbene. It turns out that the turnover frequency of propene metathesis over the Mo−P/Al2O3 catalyst is 7.1 times higher than that over the unmodified Mo/Al2O3 catalyst. The combined characterization reveals the promotion of phosphorus results from the alignment of olefin toward adjacent MoOx and thus facilitates formation of active Mo‐carbene species. [ABSTRACT FROM AUTHOR]