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Aqueous soluble and stable Cu(I) molecular catalysts featuring a catenane ligand composed of two dicationic, mutually repelling but mechanically interlocked macrocycles are reported. The ligand interlocking not only fine‐tunes the coordination sphere and kinetically stabilizes the Cu(I) against air oxidation and disproportionation, but also buries the hydrophobic portions of the ligands and prevents their dissociation which are necessary for their good water solubility and a sustained activity. These catenane Cu(I) complexes can catalyze the oxidative C−C coupling of indoles and tetrahydroisoquinolines in water, using H2O2 as a green oxidant with a good substrate scope. The successful use of catenane ligands in exploiting aqueous Cu(I) catalysis thus highlights the many unexplored potential of mechanical bond as a design element for exploring transition metal catalysis under challenging conditions. [ABSTRACT FROM AUTHOR] more...

Aim: This study aimed to develop a tool to measure paediatric specialist nurses' core competencies and examine the scale's validity and reliability. Design: An exploratory quantitative study. Methods: This study was performed in April 2022 with 302 paediatric specialist nurses in mainland China. Items were created through a literature review, a qualitative interview, and the Delphi method. The data were evaluated using descriptive statistics, independent sample t‐test, explanatory factor analysis, Pearson correlation coefficient, Cronbach's alpha coefficient and split‐half reliability. Results: The final scale consisted of five factors and 32 items. The factors were communication, coordination and judgement abilities; professional technology mastery ability; specialist knowledge mastery ability; medical‐related processes; and evidence‐based nursing competencies. The explained total variance of the five factors was 62.216%. The scale‐level and item‐level CVI of this scale was 1.00, and the mean CVR of the total scale was 0.788. The Pearson correlation coefficients of each dimension and the total dimension of the scale was 0.709–0.892, and within each dimension, it was 0.435–0.651. The Cronbach's α of this scale was 0.944, and its split‐half reliability was 0.883. [ABSTRACT FROM AUTHOR] more...

Abstract: A desymmetrizing dehydrogenation process catalyzed by a chiral primary amine is described herein. The reaction proceeds through the oxidation of a ketone enamine by IBX and enables the highly enantioselective desymmetrization of 4‐substituted cyclohexanones with the generation of chiral 4‐substituted cyclohexenones containing a remote γ‐stereocenter. [ABSTRACT FROM AUTHOR] more...

In order to optimize the creep rupture strength of Sanicro 25 welded joints, the precipitates in Sanicro 25 welded joint base metal are investigated based on the microstructural evolution during creep at 973 K, and the contribution of precipitates to the precipitation strengthening is calculated. The precipitates in the as-received Sanicro 25 welded joint base metal are primary NbCrN and MX, and creep results in the precipitation of secondary NbCrN, Cu-rich particles and M23C6. Secondary NbCrN is extremely fine and stable during creep. The precipitation strengthening of secondary NbCrN, Cu-rich particles, M23C6, and MX greatly contributes to the high creep rupture strength of Sanicro 25 welded joints. At least 58% of precipitation strengthening is contributed by secondary NbCrN and 28% is contributed by Cu-rich particles. Secondary NbCrN and Cu-rich particles are the key precipitates in improving the creep rupture strength of Sanicro 25 welded joints. [ABSTRACT FROM AUTHOR] more...

In order to optimize the strength of P92 heat-resistant steel, the variation in hardness and microstructural evolution during creep were investigated. The results show that before crept for 1429 h at 873 K, the coarsening of M23C6 is the main factor to decrease the hardness. When the creeping time prolongs from 1429 to 6063 h, the increase of hardness is mostly attributed to the precipitation of a large amount of Laves phase. Thereafter, the coarsening of Laves phase leads to the decline in hardness. The precipitation hardening resulting from MX drops distinctly in spite of the slight growth during creep. It is important to control the growth of MX, decrease the coarsening velocity of M23C6 and keep Laves phase to be fine. [ABSTRACT FROM AUTHOR] more...

The microstructural evolution of nanoerystaHine anatase TiO2 during high-energy planetary ball milling was studied. The results show that mechanical activation induces the transformations of nanoerystalllne TiO2 from anatase to srilankite and ruffle at room temperature and under ambient pressure. As the milling time increases, more anatase powder transforms to the srilankite and ruffle phase, and the particle size of the powder decreases. There is no indication of the formation of amorphous phase during ball milling. [ABSTRACT FROM AUTHOR] more...

It is demonstrated that the combination of In(OTf)3/benzoic acid efficiently catalyzes the coupling of alkynes and acetales to afford indanones in excellent yield and diastereoselectivity. [ABSTRACT FROM AUTHOR] more...

Nazarov reaction of aryl vinyl β-ketoesters is optimally catalyzed by a binary acid catalyst consisting of In(OTf)3 and diphenyl phosphoric acid (DPP). [ABSTRACT FROM AUTHOR]