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Tetrahydropyridazines constitute an important structural motif found in numerous natural products and pharmaceutical compounds. Herein, we report an aminoacylation reaction of alkenes that enables the synthesis of 1,4,5,6‐tetrahydropyridazines through cooperative N‐heterocyclic carbene (NHC) and photoredox catalysis. This approach involves the 6‐endo‐trig cyclization of N‐centered hydrazonyl radicals, generated via single‐electron oxidation of hydrazones, followed by a radical–radical coupling step. The mild process tolerates a wide range of common functional groups and affords a variety of tetrahydropyridazines in moderate to high yields. Preliminary investigations using chiral NHC catalysts demonstrate the potential of this protocol for asymmetric radical reactions. [ABSTRACT FROM AUTHOR]

The electrochemical desalination technique is recognized as a promising solution to alleviate freshwater shortages, challenges yet persists in achieving optimal energy efficiency and cost‐effectiveness. Herein, a hybrid acid/alkali zinc air desalination battery (hAA‐ZADB) capable of concurrent desalination and high‐power density is reported. To improve cathodic efficiency and cost‐effectiveness, an electrocatalyst with dual atomic Fe–Mn sites on porous dodecahedral carbon (Mn‐Fe/p‐DC) is fabricated through a simple direct pyrolysis strategy for oxygen reduction reaction (ORR). The Mn–Fe/p‐DC‐900 electrocatalyst demonstrates exceptional electrocatalytic activity (E1/2 = 0.8 V in 0.5 m H2SO4) for ORR. This innovative hybrid acid/alkali cell design, coupled with advanced electrocatalysts, empowers the hAA‐ZADB system to achieve outstanding performance benchmarks with a high open circuit voltage of 2.22 V, an impressive power density of 375 mW cm−2, and notably elevated energy output of 106.9 kJ mol−1 even at a current density of 100 mA cm−2 during desalination. Distinguishing this work is its additional functionality, evident in a rapid salt removal rate of 3.64 mg cm−2 min−1 during desalination, achieving an impressive 88.67% removal of 0.6 M NaCl. This study highlights the promising potential of employing metallic air batteries for a self‐powered desalination technique applicable to specific scenarios. [ABSTRACT FROM AUTHOR]

China has implemented a sequence of policies for clean air since year 2013 and the aerosol pollution has been substantially improved, but ozone (O3) related issues arose. Here, climate responses to changes in aerosols and O3 related to the emission reductions over China during 2013-2017 are investigated using the Community Earth System Model version 2 (CESM2). The overall decreases in aerosols produced an anomalous warming of 0.09 ± 0.10 °C in eastern China (22° N-40° N, 110° E-122.5° E), which is further enhanced by the increase in O3 in the lower troposphere, resulting in an accelerated warming of 0.16 ± 0.15 °C in eastern China. Reductions in industrial emissions contributed the most to the aerosol-induced warming, while emission reductions from residential sector induced a cooling effect due to a substantial decrease in light-absorbing black carbon aerosols. It implies that switching residential sector to cleaner energy is more effective to achieve climate and health co-benefits in China. [ABSTRACT FROM AUTHOR]

Cancer immunotherapy is a promising method for cancer therapy. Imiquimod (R837) is a molecule that could activate immune systems for cancer immunotherapy, but an easily manufactured biocompatible carrier to deliver R837 may be needed to overcome the disadvantages of R837. Micelles formed by biocompatible copolymers have been widely used to deliver chemotherapeutic drugs but not immunotherapeutic drugs. In this study, R837 was linked to an amphiphilic biodegradable copolymer mPEG‐b‐PLA via acid‐sensitive Schiff bases. The molecular structures were investigated by 1H nuclear magnetic resonance, gel permeation chromatography and Fourier transform infrared spectroscopy. The product could be self‐assembled into micelles with R837 content as high as 22.4%. Owing to acid‐cleavable Schiff bases, the release of R837 from micelles was markedly accelerated under acidic media. Consequently, the micelles linked with R837 stimulated the expression of major histocompatibility complex II‐stimulating molecules on the surface of RAW 264.7 macrophages at pH 6.5 but not pH 7.4. By using human umbilical vein endothelial cells as the in vitro model, it was shown that the polymer carriers and R837‐linked micelles were minimally cytotoxic and did not induce the activation of endothelial cells under physiological pH, which suggested the relatively high biocompatibility. In conclusion, this study successfully developed pH‐responsive immunotherapeutic drug‐loaded micelles that could activate macrophages at acidic pH in vitro. The high biocompatibility of the micelles to endothelial cells also indicated the potential uses under in vivo conditions. This study successfully developed pH‐responsive immunotherapeutic drug‐linked micelles for potential uses in cancer immunotherapy. The micelles had moderate drug content, precisely controlled molecular structure and nanoscale size. The micelles increased the solubility of R837 and activated macrophages at acidic pH due to the acid‐sensitive Schiff bases. By using human umbilical vein endothelial cells, it was shown that the micelles were minimally cytotoxic and did not induce the activation of endothelial cells under physiological pH, indicating the relatively high biocompatibility. [ABSTRACT FROM AUTHOR]

In intermediate-acid magmatic rocks, alkaline magmatic rocks, gneisses and migmatitic rocks K-feldspar is a rock-forming rock in which the contents of Pb are highest, just 2 - 10 times those of the whole rock, 3 - 16 times those of mica minerals and 6 - 32 times those of quartz. The lowest contents of K-feldspar are recognized in Early Proterozoic and Achaean rocks, with Pb in the K-feldspar accounting for less than 10% of that in the whole rock; in post-Middle Proterozoic alkaline magmatic rocks, K-feldspar-rich granites and metamorphic rocks the contents of K-feldspar tend to increase, with the proportion of Pb over that in the whole rock being obviously increased. In the alkaline rocks in which K-feldspar accounts for 50% - 70% of the total in the whole rock, the contents of Pb in K-feldspar account approximately for 70% - 95% of the total lead in the whole rock. Being accessible to hydrothermal alteration in the late periods, K-feldspar was conversed to sericite, calcite, quartz, etc. In the process of such conversion the lead would be leached out and then find its way into fluid phase. This kind of transformation can provide sufficient ore-forming material for later Pb metallogenesis. [ABSTRACT FROM AUTHOR]

The Proterozoic anorogenic magmatic rocks are well developed in the Bayan Obo deposit region. They are composed of trachyte, magnesioarfvedesonite-feldspatite, potash-rhyolite, dacite, rhyolite, quartz porphyry and trachy basalt. A lot of high-K diabase veins (dykes) are also found. These anorogenic magmatic rocks are derived from the mantle. They have lowerɛNd(t) (4.52-5.88) with T Nd DM = 1.54-1.92 Ga. Their Nd isotopic compositions and T Nd DM are consistent with those of ores, implying that the ore-forming materials were derived from these anorogenic magmatic rocks. The zircon U-Pb ages of the rocks are 1.8 Ga. Research results indicate that the Bayan Obo Group was replaced by the hydrothermal solution related to the anorogenic magmatic rocks, resulting in the formation of the deposit. [ABSTRACT FROM AUTHOR]

Methanol as a hydrogen carrier provides a practical solution for H2 storage and transport, but traditional reforming faces challenges with low efficiency, CO2 emissions, and the need for specialized infrastructure. In this study, a reliable approach for fabricating low‐cost electrodes is presented by in situ growing high‐entropy phosphide nanoparticles on nickel foam (FeCoNiCuMnP/NF). This cost‐effective design is specifically engineered for alkaline methanol oxidation reactions (MOR), achieving a current density of 10 mA cm−2 at an applied voltage of only 1.32 V, while also demonstrating exceptional selectivity for formate products. Advanced Monte Carlo (ML‐MC) simulations identify copper as the predominant surface element and highlight phosphorus coordination as a key factor in enhancing catalytic activity. The field is advanced with a pioneering hybrid acid/alkali flow electrolyzer system, integrating FeCoNiCuMnP/NF anode and commercial RuIr/Ti cathode to enable indirect hydrogen liberation from methanol. This system requires an electrolytic voltage as low as 0.58 V to achieve a current density of 10 mA cm−2 and remains stable for hydrogen liberation over 300 h of operation. This achievement not only offers a highly efficient alternative to indirectly liberate H2 stored in methanol but also establishes a new benchmark for sustainable and economically viable H2 production. [ABSTRACT FROM AUTHOR]

The development of oxygen‐dependent fuel cells is frequently hindered by the high cost of cathode materials and the sluggish kinetics of the oxygen reduction reaction (ORR). It is thus crucial to explore low‐cost and high‐activity catalysts with accelerated mass transport. Here, a high‐throughput screening method is developed by integrating an explicit solvation model with machine learning potential‐based molecular dynamics simulations, which enables the efficient evaluation of a vast array of diverse diatomic combinations and ultimately identifying Fe–Co dual‐atomic sites as the optimal ORR electrocatalysts. The superior electrocatalytic performance of the diatomic Fe/Co sites loaded on 3D‐interconnected ordered macroporous carbon (FeCo‐3DMNC) is experimentally verified, achieving high ORR activity with half‐wave potentials of 0.806 V in acidic and 0.905 V in alkaline environments. Additionally, innovative hybrid acid/alkali aluminum–air fuel cells (hA/A‐AAFCs) incorporating FeCo‐3DMNC as the cathode catalyst demonstrate a notably high open‐circuit voltage of 2.72 V and a record‐breaking power density of 827 mW cm−2, significantly outperforming conventional alkaline aluminum–air fuel cells. This work marks a significant advancement by combining cutting‐edge computational screening with rigorous experimental validation to develop promising electrocatalysts, potentially paving the way for the advanced energy storage and conversion technologies. [ABSTRACT FROM AUTHOR]

Focuses on a study on hydrothermal sedimentary mineralization and the formation of superlarge ore deposits in metallogenic belts in China. Influence factors of superlarge ore formation by hydrothermal sedimentation; Factors which controlled the element component of an ore deposit; Conclusion.

Discusses the types of mineralization of the sediment-hosted ore deposits in the reef-chert suite in China. Hydrothermal sedimentary mineralization; Hydrothermal replacing-reforming mineralization; Hydrothermal replacing-telescoping mineralization.