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The present study provided an efficient synthesis pathway to the azepino[5,4,3‐cd]indoles using N‐sulfonyl‐1,2,3‐triazoles and 4‐vinylindoles through a cascade carbene insertion and intramolecular aza‐Michael addition. This method is distinguished by mild reaction conditions, straightforward operational steps, accessible starting materials and broad substrate compatibility. Furthermore, the versatility of this reaction with various Michael acceptors significantly broadens the scope of potential substrates. The ability to further transform the resulting multifunctional products underscores the promising applications of this approach in indole nitrogen heterocyclic synthesis. [ABSTRACT FROM AUTHOR]

Inhibitors are important for flotation separation of quartz and feldspar. In this study, a novel combined inhibitor was used to separate quartz and feldspar in near-neutral pulp. Selective inhibition of the combined inhibitor was assessed by micro-flotation experiments. And a series of detection methods were used to detect differences in the surface properties of feldspars and quartz after flotation reagents and put forward the synergistic strengthening mechanism. The outcomes were pointed out that pre-mixing combined inhibitors were more effective than the addition of Ca2+ and SS in sequence under the optimal proportion of 1:5. A concentrate from artificial mixed minerals that was characterized by a high quartz grade and a high recovery was acquired, and was found to be 90.70wt% and 83.70%, respectively. It was demonstrated that the combined inhibitor selectively prevented the action of the collector and feldspar from Fourier-transform infrared (FT-IR) and adsorption capacity tests. The results of X-ray photoelectron spectroscopy (XPS) indicated that Ca2+ directly interacts with the surface of quartz to increase the adsorption of collectors. In contrast, the chemistry property of Al on the feldspar surface was altered by combined inhibitor due to Na+ and Ca2+ taking the place of K+, resulting in the composite inhibitor forms a hydrophilic structure, which prevents the adsorption of the collector on the surface of feldspar by interacting with the Al active site. The combination of Ca2+ and SS synergically strengthens the difference of collecting property between quartz and feldspar by collector, thus achieving the effect of efficient separation. A new strategy for flotation to separate quartz from feldspar in near-neutral pulp was provided. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced polyamide composites have outstanding properties, but their applications are significantly affected by the service environment. This work evaluates the effects of temperature (25, 80, 140, and 200°C) and hygrothermal conditions on the mechanical properties of CF/PA6 composite containing delamination damage, and studies its damage behaviors and failure mechanisms. After hygrothermal aging, recrystallization of PA6 improves the heat resistance of CF/PA6 composites, but water absorption reduces the interfacial strength of composites, resulting in the decrease of modulus and compressive strength (24% and 42%, respectively). With the increase in temperature, the compressive strength of CF/PA6 composites gradually decreases (from 132 MPa at 25°C to 24 MPa at 200°C), and the failure mode transitions from fiber fractures, interlayer shear fractures, delamination to kinking. In addition, the compressive failure process of CF/PA6 composites is divided into three stages: buckling, delamination bulging and kinking failure. Highlights: Hygrothermal aging reduces the fiber/resin interface performance.Fiber fracture, interlayer shear and delamination convert to kinking failure.The failure process is divided into buckling, delamination and kinking. [ABSTRACT FROM AUTHOR]

The anti-sand erosion and anti-icing coating technique is highly demanded in the leading edge of the airfoil surface. Herein, an anti-sand erosion and anti-icing coating (Si-PUEc) based on the silicone-modified polyurethane elastomer (Si-PUE) was fabricated and its hydrophobicity, tensile property, sand erosion resistance and anti-icing performance were investigated. The polyurethane elastomer was synthesized by a polyaddition reaction of hydroxy-terminated polyolefin resin and polyolefin resin as soft segments with isophorone diisocyanate and 1,4-butanediol as hard segments. The research results show that the Si-PUEc with a high water contact angle (WCA) of 108° exhibits a weak ice adhesion strength of 68.04 kPa, less than a third of that of the original bare aluminum plate surface (235.26 kPa). Moreover, the tensile strength of Si-PUEc is 14.03 MPa and the elongation at break is 370%, showing excellent tensile properties. After the sand and dust test, the surface of Si-PUEc is intact, without damage, cracking and other defects of the film, and the WCA remains at 108°. Before and after the damp-heat test, the hydrophobic performance, anti-icing performance, and stress-strain performance of Si-PUEc are not changed significantly. The distinctive composition and morphology of the polyurethane elastomer serves as the key that opens up a new strategy to design hydrophobic coatings for robust and durable anti-sand erosion and anti-icing coating applications in the leading edge of the airfoil surface.

Highlights The surface of carbon fiber is treated with sizing agent containing hydroxylated carbon nanotubes, fullerenols, and graphene oxide, respectively. The effects of carbon nanomaterials and their structures on the surface properties of carbon fiber, the interfacial properties and the mechanical properties of carbon fiber/epoxy composites are investigated. All three types of carbon nanomaterial can improve the interfacial bonding strength and modulus, thereby enhancing the interlaminar shear strength (ILSS) of composites. Moreover, the ILSS increases with the increase of interfacial bonding strength, due to the roughness and the number of active groups. Compared with the composite without carbon nanomaterials, the interfacial bonding strength of the three nanoparticle‐modified composites increased by 14%, 5% and 4%, the modulus increased by 10%, 26%, and 9%, and the ILSS increased by 14%, 8%, and 7%, respectively. The interfacial bonding strength has a more significant impact on the ILSS than the interfacial modulus. CNTs, graphene oxide and fullerenols regulate the surface characteristics of carbon fibers. The influence of carbon nanomaterials on the interfacial properties of composites. The relationship between the fiber surface, the interface and the composites. [ABSTRACT FROM AUTHOR]

Aims: To synthesize the evidence of interventions based on salutogenesis for older adults. Background: With the increasing tendency of global ageing and the progression of 'healthy ageing', salutogenesis has been adopted as a framework of health promotion for older adults. Design: An integrative review following PRISMA guidelines. Data Sources: Seven databases including PubMed, Cochrane Library, Web of Science, Embase, Scopus, PsycINFO and CINAHL Plus were systematically searched on 29 September 2022 and updated on 18 July 2023. Results: Eighteen eligible studies were included in this review. Salutogenic‐based interventions fell into three main categories: dialogue‐based, health education courses based, and goal setting and achievement based. The intervention doses: length ranged from 4 weeks to 2 years, with most (n = 12) within 12 weeks; the duration of each session ranged from 30 to 150 min, with the majority (n = 7) within 1 h; the frequency ranged from five times weekly to three times in 10 months, and in six studies was once a week. Intervention providers were mostly multidisciplinary teams, while in four studies were nurses only. Most of the studies reported that salutogenic‐based interventions could improve older adults' sense of coherence, quality of life, self‐efficacy, self‐management, meaning of life and mental health. Conclusions: This review synthesized the interventions based on salutogenesis for older adults, including salutogenesis application, intervention and its doses, intervention settings and providers, and intervention effects. Future research on the effectiveness of the intervention, the optimal dose of the intervention and the underlying mechanisms are still necessary to understand salutogenic‐based interventions. No Patient or Public Contribution: Not apply as it's a review paper. Relevance to Clinical Practice: Salutogenic‐based intervention is effective for older adults in different scenarios to improve their health outcomes. Nurses play a key role in salutogenic‐based interventional programs and thus should be essential personnel as the intervention provider. [ABSTRACT FROM AUTHOR]