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Dip catalysts, in which the catalytic species are immobilized on solid planar supports, have drawn increasing attention due to their ease of fabrication, excellent catalytic performance, convenient separation and reusability, and environmental friendliness. A special feature is that they can turn the reaction on/off instantly by simple insertion/removal from the reaction medium. Embedding metal catalysts in biodegradable films that act as dip catalysts in organic reactions is relatively new, and therefore the facilitation of their use is necessary. Biodegradable carboxymethylcellulose (CMC) and polyvinyl alcohol (PVA) have film-forming properties due to their inter/intramolecular hydrogen bonds between numerous carboxylic and hydroxy groups. Citric acid (CA), a biodegradable tricarboxylic acid, is widely used as a crosslinker due to its esterification of hydroxy groups of polymers. To obtain biodegradable dip catalysts, we propose the incorporation of CA into a CMC–PVA composite film to enhance mechanical strength through cross-linking CMC and PVA, and to provide sufficient carboxylic and hydroxy groups for the coordination of Cu(II) and Pd(II) ions, thereby yielding Cu@CMC–CA–PVA and Pd@CMC–CA–PVA dip catalysts. Both dip catalysts were extensively characterized using ICP-AES, XPS, FT-IR, XRD, TGA, FE-SEM, TEM, and EDS analysis. The XPS analysis confirmed Cu(I) in the fresh Cu@CMC–CA–PVA catalyst, while the used sample exhibited a mixture of Cu(I) and Cu(II), likely due to partial oxidation of Cu(I) during the reaction under air conditions. Similarly, Pd(II) ions immobilized on the fresh Pd@CMC–CA–PVA were reduced to Pd(0) nanoparticles (NPs) by hydroxy groups of CMC and PVA with a high average diameter distribution of 6.53 nm. The catalytic activity of both dip catalysts was firstly evaluated separately for the aldehyde-alkyne-amine (A3) coupling reactions and Suzuki–Miyaura cross-couplings. The results demonstrated that both Cu@CMC–CA–PVA and Pd@CMC–CA–PVA catalysts have good catalytic activity to give excellent yields. In addition, these dip catalysts were easily retrieved with tweezers from the reaction system to turn off reaction and re-introduced in successive batches to turn on the reaction for repeated use. After six recycles, the catalysts still maintain good performance without noticeable loss in catalytic activity. These facilely prepared, conveniently deployed, highly active, good recyclable, and eco-friendly dip catalysts are expected to hold promise as practical tools in organic synthesis. A composite film comprising carboxymethylcellulose (CMC), polyvinyl alcohol (PVA), and citric acid (CA) enables the fabrication of Cu@CMC–CA–PVA and Pd@CMC–CA–PVA dip catalysts, featuring sufficient carboxylic and hydroxy groups for coordination with Cu(II) and Pd(II) ions, respectively. Both catalysts exhibit strong activity in A3 coupling reactions and Suzuki–Miyaura cross couplings. [ABSTRACT FROM AUTHOR]

Background: Understanding how to improve mental health literacy is conducive to maintaining and promoting individuals' mental health and well-being. However, to date, interventions for mental health literacy primarily depend on traditional education and contact interventions, which have limitations with regard to pertinence and individualization. Artificial intelligence (AI) and big data technology have influenced mental health services to be more intellectual and digital, and they also provide greater technical convenience for individualized interventions for promoting mental health literacy. However, there is relatively little research on the effectiveness of individualized online intervention for mental health literacy in the literature. This study aims to fill this void. To verify whether individualized online intervention can improve the level of mental health literacy. Methods: We conducted a pretest–post-test control experiment. The participants were recruited from a large community located in central China. A total of 152 participants completed the research. We use mixed linear model estimation and paired t -tests to analyze the data. Results: Individualized online intervention can effectively improve the mental health literacy level of participants. Specifically, we found that compared with the control group, the mental health literacy in the experimental group was significantly improved after receiving individualized online intervention. Likewise, the mental health literacy of the control group has also improved after receiving individualized online intervention. In addition, we compared the mental health literacy level of the experimental group at Time 3 to those at Time 2 and found that the mental health literacy level at Time 3 had not decreased one month later. This shows that individualized online intervention was not only momentarily effective, but also had long-term efficacy. Conclusion: This study illustrates that the individualized online intervention has both great momentary and long-term effectiveness in improving community residents' mental health literacy. [ABSTRACT FROM AUTHOR]

A new Pd/Cu bimetal catalyst supported on carboxymethylcellulose/polyaniline (CMC/PANI) composites (Pd/Cu@CMC/PANI) was fabricated to investigate the cooperative effect between Pd/Cu bimetals in Sonogashira reactions. This approach involves the self‐organization of aniline on CMC via H‐bond, enabling in situ oxidative polymerization using Pd(II) and Cu(II) ions as co‐oxidants. Subsequently, Pd and Cu are self‐deposited on the resulting CMC/PANI composites through the interaction of coordination and metathesis. The morphological and compositional analysis of the prepared catalyst was performed using various analytical tools such as ICP‐AES, FT‐IR, XPS, SEM, TEM, EDS, elemental mapping, and TGA. The Pd/Cu@CMC/PANI composite as a cooperative catalyst for the Sonogashira couplings exhibited high catalytic activity with relatively low Pd loading over its monometallic Pd counterpart, demonstrating the cooperative effect between Pd and Cu. Then, this bimetallic catalyst was successfully adapted for Sonogashira‐cyclization tandem reaction for the synthesis of benzofuran with excellent yields. Significantly, the Pd/Cu@CMC/PANI catalyst exhibited thermal stability under the reaction conditions and could be easily retrieved and reused repeatedly for five runs in the model reaction without significant discernible performance degradation. [ABSTRACT FROM AUTHOR]