Here, we report a conceptual strategy for introducing spatial sulfur (S)–bridge ligands to regulate the coordination environment of Fe-Co-N dual-metal centers (Spa-S-Fe,Co/NC). Benefiting from the electronic modulation, Spa-S-Fe,Co/NC catalyst showed remarkably enhanced oxygen reduction reaction (ORR) performance with a half-wave potential ( E 1/2 ) of 0.846 V and satisfactory long-term durability in acidic electrolyte. Combined experimental and theoretical studies revealed that the excellent acidic ORR activity with a remarkable stability observed for Spa-S-Fe,Co/NC is attributable to the optimal adsorption-desorption of ORR oxygenated intermediates achieved through charge-modulation of Fe-Co-N bimetallic centers by the spatial S-bridge ligands. These findings provide a unique perspective to regulate the local coordination environment of catalysts with dual-metal-centers to optimize their electrocatalytic performance.

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Summary The design of a new type of electroreduction mixer-settler for the partitioning of uranium and plutonium during the Purex process, which is featured with E-shaped cathodes and U-shaped anodes in settling chamber, is described and the operational results achieved using this equipment are presented. The results show that this new type of mixer-settler has excellent separation performances. The flow rate of organic feed solution is 3 mL/min and the flow ratio of feed solution (1BF) to aqueous back extraction stream (1BX) and to organic wash stream (1BS) is 4/1/1. For an organic feed of 84 g/L uranium and 1.40 ⁓ 2.64 g/L plutonium, both the separation factor of plutonium from uranium and that of uranium from plutonium are apparently higher than 104

The purpose of this study is to prepare 99mTc‐diaminoethylpropane diamine haxaacetic acid and clarify its renal excretion mechanism. BPHA obtained from chemical synthesis and characterized by IR and MS was labeled with technitium‐99m. The renal excretion mechanism was determined by probenecid inhibition experiment. The radioactivity remained in the body at different time point postinjection was measured by a γ detector. Renal dynamic imaging of rabbit and human was performed using a γ camera. For all the experiments 99mTc‐DTPA was also examined as contrast. Similar to 99mTc‐DTPA, 99mTc‐BPHA was excreted with a glomerular excretion mechanism. After 24 h, 99mTc‐BPHA remained in the body was very little. Kidney imaging of rabbit and volunteer showed excellent kidney images and fast 99mTc‐BPHA excretion. The results showed that the self‐made 99mTc‐BPHA appeared to be a glomerular filtration imaging agent satisfying clinical requirement and an alternative to 99mTc‐DTPA.