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Comparison of the structural features and catalytic performance of bimetallic nanocatalysts will help to develop a unified understanding of structure–reaction relationships. The single-molecule fluorescence technique was utilized to reveal the differences in catalytic kinetics among PtRu bimetallic nanocatalysts and Pt and Ru monometallic nanocatalysts at the single particle level. The results show that bimetallic nanocatalysts have higher apparent rate constants and desorption rate constants relative to monometallic nanocatalysts, which leads to their higher catalytic activity. At the single particle level, bimetallic nanocatalysts have a wider distribution of apparent rate constants, suggesting that bimetallic nanocatalysts have higher activity heterogeneity relative to monometallic nanocatalysts. By investigating the relationship between the reaction rate and the rate of dynamic activity fluctuations, it was found that spontaneous surface restructuring and reaction-induced surface restructuring of nanoparticles occurred. The surface of bimetallic nanoparticles restructured faster, which made the bimetallic nanocatalysts more active. These findings provide new insights into the design of highly active bimetallic nanocatalysts. [ABSTRACT FROM AUTHOR]

Accurate water content detection is crucial for optimizing chemical reactions, ensuring product quality in pharmaceutical manufacturing, and maintaining food safety. In this study, nitrogen and sulfur co-doped graphene quantum dots (R-GQDs) were synthesized via a one-step hydrothermal method using o-phenylenediamine as the carbon source. The synthesis conditions, including reaction time, temperature, o-phenylenediamine concentration, and H2SO4/water ratio, were optimized using the Box-Behnken response surface methodology. The R-GQDs exhibited excellent fluorescence stability and distinct solvent-dependent characteristics, alongside a broad linear detection range and high sensitivity, making them highly suitable for dual-mode water content detection (colorimetric and fluorescent). To enhance the accuracy of visual detection, R-GQDs were incorporated into portable test strips with smartphone-assisted analysis, compensating for the human eye's limitations in distinguishing subtle color changes. The sensor's practical utility was validated through spiked recovery experiments in food samples, and the R-GQDs demonstrated good biocompatibility for in vivo imaging in shrimp. These findings highlight a novel strategy for developing portable, real-time water content sensors with potential applications in both portable detection systems and biological imaging. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate functional outcomes of robot-assisted ureteroplasty with labial mucosa grafting for long proximal ureteral stenosis (LPUS) in children and adolescents. Methods: Included in this study were 15 patients who underwent robot-assisted ureteroplasty with labial mucosal grafting in our center between July 2017 and September 2021. The left affected stenotic ureter was repaired using labial mucosal grafting. If the ureter was simply strictured but not obliterated, the ureter was spatulated longitudinally along the ventral side and the labial mucosa graft was interposed and anastomosed in a continuous manner. Faced with the obliterated segment, it was excised and the spatulated portion re-anastomosed with a pelvic flap as the dorsal wall. The labial mucosa graft was placed as the ventral wall. The preoperative clinical data and follow-up outcomes were collected and evaluated. Results: Labial mucosa graft onlay ureteroplasty was well performed in all the 15 patients with no occurrence of intraoperative complications or surgical conversion. Five patients underwent an onlay ureteroplasty, and 10 patients underwent a dorsally augmented pelvic flap anastomotic ureteroplasty. The mean (range) stricture length was 7.1 (3–10) cm. The mean operative time was 371.2 (216–480) minutes, and the median blood loss was 40 mL. At the median follow-up of 35 months (range 12–58 months), the overall success rate was 93.3%. Conclusions: Labial mucosa grafting appears to be safe and feasible for repairing long ureteral strictures in pediatric and adolescent patients. Our experience may provide beneficial references and conveniences to solve complex problems in LPUS. This study was approved by the institutional review board, and written informed consent was obtained from each participant (ethics number: 2017-30). [ABSTRACT FROM AUTHOR]