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Membrane separation has become an indispensable separation technology in social production, playing an important role in drug production, mineral exploitation, water purification, etc. The key core of membranes lies in achieving efficient and precise sieving between substances. As a result, a typical trade‐off arises: highly permeable membranes usually sacrifice selectivity and vice versa. To address this dilemma, long‐term research has focused on comprehensive understanding and modelling of synthetic membranes at various scales. A significant advancement in this arena is the advent of three‐dimensional covalent organic framework (3D COF) membranes, a novel category of long‐range ordered porous organic polymer materials. Characterized by an abundance of interconnected channels, diverse pore wall properties, tunable structures, and robust thermal and chemical resilience, 3D COF membranes offer a promising approach for efficient substance separation. This review undertakes a meticulous investigation of the synthesis and physicochemical properties of 3D COF membranes, accentuating the underlying design principles, fabrication methods, and application attempts. A comprehensive assessment of their research trajectory and current standing in the field of membrane processes is provided. The review culminates in a forward‐looking outlook, summarizing future research directions and highlighting the substantial potential of this innovative work to shape the future of efficient membrane separation processes. [ABSTRACT FROM AUTHOR]

The fir‐tree tenon/mortise structure in areo‐engine suffers from the combined high and low cycle fatigue (CCF) loads during service. The structural integrity of the tenon/mortise structure is significantly affected by the local strain distribution, while the strain value under the CCF loads is difficult to acquire. In this study, a simulated specimen of tenon/mortise structure is designed, and the CCF test is carried out using a divided‐path loading fixture to avoid interference between the high cycle fatigue (HCF) loads and the low cycle fatigue (LCF) loads. The high speed digital image correlation (DIC) method is adopted to acquire the real‐time strain distribution during CCF test. According to the strain results, the critical position of the mortise and its strain variation are determined. The high cycle strain of the mortise is proportional to the vibration amplitude of the tenon. The experimental results can provide basis for strength and life assessment. Highlights: A combined high and low fatigue test system is designed to study the strain variation.The real‐time strain distribution is obtained by high speed digital image correlation (DIC) method.The strain exhibits sinusoidal variations when applied to the combined high and low cycle fatigue (CCF) loads. [ABSTRACT FROM AUTHOR]

This study investigated the relationship between fracture toughness (Kc) and energy release rate (Gc) through fracture morphology analysis, emphasizing the critical role of fractal dimensions in accurately characterizing fracture surfaces. Traditional linear elastic fracture mechanics (LEFM) models relate Gc to Kc by combining energy principles with the nominal area of the fracture surface. However, real materials often exhibit plasticity, and their fracture surfaces are not regular planes. To address these issues, this research applied fractal theory and introduced the concept of ubiquitiform surface area to refine the calculation of fracture surfaces, leading to more accurate estimates of Gc and Kc. The method was validated through standard compact tensile specimen tests on a nickel-based superalloy at 550 °C. Additionally, the analysis of fractal dimension differences and dispersion in various fracture regions provides a novel perspective for evaluating the fracture toughness of materials. [ABSTRACT FROM AUTHOR]

Membranes are important in the pharmaceutical industry for the separation of antibiotics and salts. However, its widespread adoption has been hindered by limited control of the membrane microstructure (pore architecture and free‐volume elements), separation threshold, scalability, and operational stability. In this study, 4,4′,4′′,4′′′‐methanetetrayltetrakis(benzene‐1,2‐diamine) (MTLB) as prepared as a molecular building block for fabricating thin‐film composite membranes (TFCMs) via interfacial polymerization. The relatively large molecular size and rigid molecular structure of MTLB, along with its non‐coplanar and distorted conformation, produced thin and defect‐free selective layers (~27 nm) with ideal microporosities for antibiotic desalination. These structural advantages yielded an unprecedented high performance with a water permeance of 45.2 L m−2 h−1 bar−1 and efficient antibiotic desalination (NaCl/adriamycin selectivity of 422). We demonstrated the feasibility of the industrial scaling of the membrane into a spiral‐wound module (with an effective area of 2.0 m2). This module exhibited long‐term stability and performance that surpassed those of state‐of‐the‐art membranes used for antibiotic desalination. This study provides a scientific reference for the development of high‐performance TFCMs for water purification and desalination in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Covalent organic framework (COF) membranes featuring uniform topological structures and devisable functions, show huge potential in water purification and molecular separation. Nevertheless, the inability of uniform COF membranes to be produced on an industrial scale and their nonenvironmentally friendly fabrication method are the bottleneck preventing their industrial applications. Herein, we report a new green and industrially adaptable scraping‐assisted interfacial polymerization (SAIP) technique to fabricate scalable and uniform TpPa COF membranes. The process used non‐toxic and low‐volatility ionic liquids (ILs) as organic phase instead of conventional organic solvents for interfacial synthesis of TpPa COF layer on a support membrane, which can simultaneously achieve the purposes of (i) improving the greenness of membrane‐forming process and (ii) fabricating a robust membrane that can function beyond the conventional membranes. This approach yields a large‐area, continuous COF membrane (19×25 cm2) with a thickness of 78 nm within a brief period of 2 minutes. The resulting membrane exhibited an unprecedented combination of high permeance (48.09 L m−2 h−1 bar−1) and antibiotic desalination efficiency (e.g., NaCl/adriamycin separation factor of 41.8), which is superior to the commercial benchmarking membranes. [ABSTRACT FROM AUTHOR]