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BackgroundWith aging deepening, there is an increasing demand for medical and elderly care services in Chinese older residents. However, current medical and pension services are still in a state of disconnection. In this regard, integrated medical and nursing care could continuously satisfy their multi-level healthcare needs via orderly combining medical and nursing care resources.ObjectiveTo comprehensively analyze the willingness of Chinese elderly residents to use integrated medical and nursing care.MethodsThe literature on the willingness of Chinese elderly residents to use integrated medical and nursing care was searched in databases including CNKI, WanFang Data, CQVIP, PubMed and Web of Science from inception to December, 2020. Data of studies satisfying the inclusion criteria were extracted and meta-analyzed. The literature quality was evaluated by using the current situation survey bias risk assessment criteria (JBI) .ResultsA total of 20 articles were included. The effective sample size of the study was 14 089 cases, and 4 268 residents were willing to participate. The JBI scores of the literature included in the study were 14-18 points, which were greater than 70% of the total score. The quality of the literature included in the study was high. The overall rate of Chinese elderly residents' willingness to use integrated medical and nursing care was 40.5%〔95%CI (33.3%, 47.7%) 〕. Results of subgroup analysis demonstrated that educational background〔OR (95%CI) =0.71 (0.59, 0.85) , P

Abstract\nThe inherent brittleness of unidirectional fiber-reinforced composites represents a major complication in their broad practical applications. However, exploiting different reinforcement architectures can offer an opportunity for highly desirable ductile fracture nature. This article is aimed at investigating experimentally the tensile behavior of an epoxy laminate reinforced by different layers of plain weft-knitted fabrics. The fabricated laminates were subjected to uniaxial tension in different loading directions, and the corresponding tensile responses were recorded. Basic mechanical properties were characterized and digital image correlation (DIC) was employed to capture surface deformations. Tensile test results demonstrated strong nonlinearity and pseudo-ductility as well as loading-direction dependence in this type of composite laminates. Fracture tests were conducted showing high fracture toughness ranging from 10 to 20 MPa·m1/2. Typical damage modes were characterized using microscopy, which were coupled to a few distinct tensile deformation stages. This work demonstrates that weft-knitted composites are promising in permitting great amounts of pseudo-ductility with clear warning before complete failure. It is also expected to contribute to the understanding of the specific role of weft knit fabrics in composite laminates.Analysis of the deformation process of plain weft-knitted composites and various failure modes by DIC and microscopy.Observation and explanation of pseudo-ductility in the knitted composites subjected to off-axis tension.Translaminar fracture toughness measured by over-height compact tension (OCT) specimens. Flaw insensitive length scale estimated on the order of 10 mm.Yarn loop reorientation permitted by matrix plasticity contributing to identified stiffening in off-axis specimens. [ABSTRACT FROM AUTHOR]

2D fiber reinforced resin matrix composites (2D FRRMC) are widely applied for aerospace, generator blades, and other high‐end equipment manufacturing fields due to their excellent mechanical properties. However, 2D FRRMC will face a variety of complex environments in the service process, and the long‐term complex environment will significantly impact the physical and mechanical properties of 2D FRRMC. It is necessary to understand and analyze the changes of materials during service. A comprehensive review of the research on the effect of hydrothermal aging on the mechanical properties and re‐ drying of 2D FRRMC in recent years was presented in this article, which contains interlaminar shear properties, compression properties, tensile properties, and aging mechanism, etc. Finally, the current challenges and prospects of 2D FRRMC were discussed. These discussions and proposed strategies will enlighten thoughts and offer ways to apply 2D FRRMC in complex environments better, study 2D FRRMC in complex environments, and study the effects of hydrothermal aging on materials in the future. [ABSTRACT FROM AUTHOR]

Three‐dimensional (3D) braided composites have good integrity and high stability, but aramid fiber (AF) has an inert surface and poor interfacial bonding with resin, which affects the mechanical properties of aramid 3D braided composites and limits their development. This paper used catechol/pyrogallol polyamine (CA/PGPA) to modify the AF. The effects of different mass fraction ratios of CA/PGPA and different reaction temperatures on the surface properties of AF and the mechanical properties of 3D braided composites were investigated. The results showed that after the CA/PGPA modification, fiber surface oxygen‐containing groups increased, the roughness became more extensive, the fiber strength increased, and the interfacial shear strength increased. When AF‐CAPG‐II‐40°C, the mechanical properties of the 3D braided composites were improved most significantly. Compared with unmodified composites, the bending modulus was increased by 70%, the compression modulus by 124%, and the shear strength by 55.7%. The epoxy resin modification was carried out based on AF‐CAPG‐II‐40°C, and when the mass fraction of aramid nanofiber/graphene nanoparticle (ANF/G) was 0.7 wt%, 3D braided composites exhibited satisfactory mechanical properties. The bending modulus, compression modulus, and shear strength were increased by 15.3%, 23.3%, and 25.7%, respectively, compared with AF‐CAPG‐II‐40°C. [ABSTRACT FROM AUTHOR]

Aramid fibers and ultra‐high molecular weight polyethylene (UHMWPE) fibers lack active surface functional groups, and the surface is smooth, limiting their practical application in textile composite materials. In this study, zinc oxide nanorods were used to grow on aramid fibers surfaces, and oxygen plasma followed by treatment with a silane coupling agent was used to modify UHMWPE fibers. The effects of surface modification on the surface morphology and composition, and mechanical properties of fibers and composites were investigated. The mechanical response of interlayer hybrid textile composite materials based on modified aramid and UHMWPE fabrics was examined. The results reveal that surface roughness, active surface functional groups, and wettability that can be controlled by treatment conditions and parameters are important for improving interface adhesion. In addition, the interlayer hybridization pattern as a result of using dissimilar layer materials and altering stacking sequence has a great impact on the mechanical behavior of hybrid textile composite materials. [ABSTRACT FROM AUTHOR]

In this study, silica-coated zinc oxide nanoparticles (NPs) were prepared via a sol-gel method using inorganic NPs with an organic polymer binding. A hybrid coating was formed with epoxy resin to form a core-shell structure on the fiber surface to improve the interfacial properties between the fiber and resin. The results showed that there was no decrease in the tensile strength of the fiber and the interfacial shear strength with the epoxy resin increased by 38.26 % compared to the pristine sample. The addition of a silane coupling agent played an active role in improving the interfacial properties. Infrared spectroscopy and X-ray diffraction analysis revealed that chemical bonds formed between ZnO and SiO2. Scanning electron microscopy showed that the SiO2-coated ZnO NPs polymer composite formed a uniform film particle layer on the surface of the aramid fibers. With this method, it is possible to design aramid fiber composites with good interfacial properties. [ABSTRACT FROM AUTHOR]