Plastic Resistance Research Articles

S6K1 is a Targetable Vulnerability in Tumors Exhibiting Plasticity and Therapy Resistance.

Background: Most tumors initially respond to treatment, yet refractory clones subsequently develop owing to resistance mechanisms associated with cancer cell plasticity and heterogeneity. Methods: We used a chemical biology approach to identify protein targets in cancer cells exhibiting diverse driver mutations and representing models of tumor lineage plasticity and therapy resistance. An unbiased screen of a drug library was performed against cancer cells followed by synthesis of chemical analogs of the most effective drug. The cancer subtype target range of the leading drug was determined by PRISM analysis of over 900 cancer cell lines at the Broad Institute, MA. RNA-sequencing and enrichment analysis of differentially expressed genes, as well as computational molecular modeling and pull-down with biotinylated small molecules were used to identify and validate RPS6KB1 (p70S6K or S6K1) as an essential target. Genetic restoration was used to test the functional role of S6K1 in cell culture and xenograft models. Results: We identified a novel derivative of the antihistamine drug ebastine, designated Super-ebastine (Super-EBS), that inhibited the viability of cancer cells representing diverse KRAS and EGFR driver mutations and models of plasticity and treatment resistance. Interestingly, PRISM analysis indicated that over 95% of the diverse cancer cell lines tested were sensitive to Super-EBS and the predicted target was the serine/threonine kinase S6K1. S6K1 is upregulated in various cancers relative to counterpart normal/benign tissues and phosphorylated-S6K1 predicts poor prognosis for cancer patients. We noted that inhibition of S6K1 phosphorylation was necessary for tumor cell growth inhibition, and restoration of phospho-S6K1 rendered tumor cells resistant to Super-EBS. Inhibition of S6K1 phosphorylation by Super-EBS induced caspase-2 dependent apoptosis via inhibition of the Cdc42/Rac-1/p-PAK1 pathway that led to actin depolymerization and caspase-2 activation. The essential role of S6K1 in the action of Super-EBS was recapitulated in xenografts, and knockout of S6K1 abrogated tumor growth in mice. Conclusion: S6K1 is a therapeutic vulnerability in tumors exhibiting intrinsic and/or acquired resistance to treatment.

Evolution of Surface Integrity Characteristics and Mechanical Behavior of Diamond Burnished and Turned AISI 304 Steel Specimens After Prolonged Exposure to Natural Seawater

This article presents results on the evolution of surface integrity, microstructure, mechanical characteristics, fatigue strength, and wear behavior of AISI 304 steel specimens after prolonged exposure (up to 746 days) to a natural seawater environment, specifically near the port of Varna, Bulgaria. The samples, having different shapes and sizes according to the respective tests, were divided into two main groups based on the finishing process: fine turning (FT) and diamond burnishing (DB). Additionally, fatigue FT specimens were polished to meet the standard requirements. Some of the cylindrical samples from both groups were heat-treated to dissolve the car-bides. No significant improvement in the corrosion resistance of the heat-treated samples (FT and DB) was observed compared with untreated samples after 746 days of immersion in seawater. Overall, all types of DB specimens showed less mass loss (indicating a higher corrosion resistance), higher static and fatigue strength, greater plasticity, and greater wear resistance than the corresponding FT specimens. Notably, pitting corrosion was observed on all specimens, as well as trac-es of intergranular corrosion in some FT specimens. The hardening DB effects have a complex impact on corrosion activity. The increases in dislocation density and the surface and internal energy of the subsurface layers intensify the nucleation of corrosion centers in the surface layers; however, the refined fibrous structure and significant reduction in the roughness slow down the development of corrosion. Therefore, the implementation of DB as a smoothing process will re-duce the surface energy, and hence will lead to further increases in corrosion resistance.

Geomechanical and Hydraulic Behavior of Impermeable Layers for Earthworks

Objective: The objective of this study is to investigate the mechanical and hydraulic behavior of fine sandy soil mixtures from the Coastal Plain of Rio Grande do Sul with bentonite, assessing their technical feasibility as an impermeable layer for earthwork projects. Theoretical Framework: El marco teórico explora la impermeabilización de vertederos sanitarios, destacando la eficacia de los liners para contener contaminantes y el uso de bentonita como aditivo para suelos granulares. Estudios previos señalan mejoras en la conductividad hidráulica y la plasticidad de mezclas de suelo-bentonita, especialmente en regiones con escasez de materiales arcillosos de alta calidad. Method: The method includes laboratory tests with natural soil and mixtures containing different bentonite contents. Physical, granulometric, plasticity, compaction, hydraulic conductivity, and mechanical resistance properties were evaluated. Results and Discussion: The natural soil proved unsuitable for use as an impermeable layer. The results show that the addition of bentonite significantly improved the soil's hydraulic conductivity, with 6% by dry weight achieving values suitable for impermeable layers. However, increasing bentonite content reduced the friction angle, indicating a decrease in mechanical strength. Research Implications: The research highlights the potential of soil-bentonite mixtures as a sustainable solution for impermeable layers in earthwork projects, particularly in regions with limited availability of clayey soils. The results provide technical support for the use of local materials, contributing to the feasibility of environmental engineering projects tailored to regional characteristics. Originality/Value: The research is original in exploring soil-bentonite mixtures as a sustainable solution for impermeable layers in coastal plains, a region with scarce suitable clayey soils. Its contribution lies in the technical evaluation of local materials, promoting innovative and environmentally adapted alternatives for engineering projects in challenging contexts.

ABCG1 orchestrates adipose tissue macrophage plasticity and insulin resistance in obesity by rewiring saturated fatty acid pools.

The mechanisms governing adipose tissue macrophage (ATM) metabolic adaptation during diet-induced obesity (DIO) are poorly understood. In obese adipose tissue, ATMs are exposed to lipid fluxes, which can influence the activation of specific inflammatory and metabolic programs and contribute to the development of obesity-associated insulin resistance and other metabolic disorders. In the present study, we demonstrate that the membrane ATP-binding cassette g1 (Abcg1) transporter controls the ATM functional response to fatty acids (FAs) carried by triglyceride-rich lipoproteins, which are abundant in high-energy diets. Mice genetically lacking Abcg1 in the myeloid lineage presented an ameliorated inflammatory status in adipose tissue and reduced insulin resistance. Abcg1-deficient ATMs exhibited a less inflammatory phenotype accompanied by a low bioenergetic profile and modified FA metabolism. A closer look at the ATM lipidome revealed a shift in the handling of FA pools, including a redirection of saturated FAs from membrane phospholipids to lipid droplets, leading to a reduction in membrane rigidity and neutralization of proinflammatory FAs. ATMs from human individuals with obesity presented the same reciprocal relationship between ABCG1 expression and this inflammatory and metabolic status. Abolition of this protective, anti-inflammatory phenotype in Abcg1-deficient ATMs was achieved through restoration of lipoprotein lipase (Lpl) activity, thus delineating the importance of the Abcg1/Lpl axis in controlling ATM metabolic inflammation. Overall, our study identifies the rewiring of FA pools by Abcg1 as a major pathway orchestrating ATM plasticity and insulin resistance in DIO.

EpiCHAOS: a metric to quantify epigenomic heterogeneity in single-cell data

Epigenetic heterogeneity is a fundamental property of biological systems and is recognized as a potential driver of tumor plasticity and therapy resistance. Single-cell epigenomics technologies have been widely employed to study epigenetic variation between—but not within—cellular clusters. We introduce epiCHAOS: a quantitative metric of cell-to-cell heterogeneity, applicable to any single-cell epigenomics data type. After validation in synthetic datasets, we apply epiCHAOS to investigate global and region-specific patterns of epigenetic heterogeneity across diverse biological systems. EpiCHAOS provides an excellent approximation of stemness and plasticity in development and malignancy, making it a valuable addition to single-cell cancer epigenomics analyses.

Thermal Debromination-Induced Cross-Linking of PIM-Polyimide Membranes: Improved CO2 Gas Permeability, Selectivity, and Separation Performance

Demand for advanced polymers with intrinsic microporosity (PIM) is growing due to their enhanced free volume and potential in gas separation membranes. However, PIM-based membranes are vulnerable to aging effects and loss of stable performance. To overcome this drawback, we synthesized a PIM-polyimide (PI) polymer based on PIM-dianhydride and a durene diamine unit (PIM-PI-1). Bromination at the PIM-PI-1 benzyl positions provided PIM-PI-Br–Z (bromination degree Z = 15, 25, and 50 %), precursors for thermal debromination-induced cross-linking. The optimal cross-linked membrane derived from 50 % brominated PIM-PI-Br–50 demonstrated remarkable CO2 permeability (5401 Barrer) combined with good CO2/CH4 (21.1) and CO2/N2 (21.0) selectivity, surpassing the 2008 upper bound. Additionally, the membrane demonstrated good performance in mixed gas tests (CO2/N2), exhibiting a CO2 permeability of 2299 Barrer and CO2/N2 selectivity of 31. The thermally cross-linked membrane exhibited promising anti-aging properties up to 13 days and excellent CO2-induced plasticization resistance even under pressures up to 18 atm, demonstrating its potential for high-performance PIM-based gas separation membranes.

Epitranscriptomics in oncology: The double-edged role of RNA modifications in cancer and resistance

Epitranscriptomics, the study of RNA modifications such as N6-methyladenosine (m6A), has emerged as a pivotal field in cancer research. These chemical modifications influence gene expression, protein translation and cellular behavior, driving critical processes like tumor initiation, progression and metastasis. Furthermore, RNA modifications contribute to cancer stem cell plasticity, promoting survival and therapy resistance. Treatment resistance, a major obstacle in cancer therapy, is often driven by aberrant RNA modifications that affect the stability of coding and non-coding RNAs, leading to enhanced DNA repair, drug efflux and immune evasion. As a result, targeting RNA-modifying enzymes has gained attention as a novel therapeutic strategy. Inhibitors of "writers," "erasers" and "readers" of these modifications are currently being explored to restore sensitivity to conventional therapies. This commentary discusses the emerging role of RNA modifications in cancer progression and treatment resistance, highlighting the potential for novel therapeutic interventions in combatting drug-resistant cancers.

Research on Mechanical Properties of High‐Manganese Steel Coating Manufactured by Coaxial Powder‐Feeding Laser Cladding

Due to the process complexity of the high‐carbon high‐manganese steel (HMnS) in casting and arc welding, this article propose the coaxial powder‐feeding laser cladding (LC) of HMnS coating using self‐developed HMnS powders. Firstly, high‐carbon HMnS coatings are prepared on the 16Mn substrate using coaxial powder‐feeding LC technology. It has a single austenite phase, without large defects such as pores and cracks. Then, ultrasonic shock peening is used to harden the HMnS coating, and the mechanical properties such as microhardness, impact toughness, wear and tensile properties are measured, which prove that HMnS coating has excellent working hardening, plasticity, toughness, and wear resistance properties. Finally, transmission electron microscopy is used to investigate the coupling effects such as dislocations, multiple twinning, and stacking faults on the HMnS coating after tensile fracture (true strain 39.2%). The deformation strengthening mechanism based on the dynamic Hall–Petch effect is revealed. The research results provide a new method for the preparation of high‐carbon HMnS coatings, and a new idea for expanding the application of high‐carbon HMnS.

Synthesis and characterization of polyimides with rigid folded fragments

The macromolecular chain of conventional polyimide (PI) is a predominant linear extension, which is anticipated to uphold robust interchain interactions essential for preserving overall mechanical and thermal performance. This study is dedicated to the design and synthesis for the novel PIs containing folded chains, with a particular emphasis on modifying the chain conformational behavior with respect to the structure of the aggregation state and the corresponding gas separation properties. First, two unidirectional diamine monomers, dibenzo [c, g] phenanthrene-9,12-diamine (NPDA) and anthracene-1,8-diamine (ADA), were meticulously synthesized through a sequence of chemical reactions, including Witting olefination and photocyclization. These monomers possess distinctive spatial characteristics: NPDA adopts a helical conformation, while ADA maintains a planar structure. Subsequently, the corresponding folded chain-containing PIs, denoted as NPI and API, were successfully achieved by copolymerizing one of the unidirectional monomers with the 6FDA-TPDA system. API and NPI generally exhibit a propensity for enhanced molecular chain stacking, while retaining their good solubility and processability. Drawing from both experimental data and simulation results, it was ascertained that the inclusion of these two monomers produces a rearrangement of pore sizes with a decrease in large-size micropores and an increase in the percentage of ultra-micropores. Moreover, the PI membranes with the folded fragments have a much better CO2 plasticization resistance.

Enhanced plasticization resistance of hollow fiber membranes via metal ion coordination for advanced helium recovery

Plasticization can significantly impair the gas separation performance of gas separation membranes, especially for hollow fiber membranes (HFMs) with ultrathin skin layer. While conventional thermal crosslinking is an effective method to address this issue, it often leads to the transition layer collapse in HFMs, resulting in a significant decrease in gas permeance. Herein, we fabricate polyimide-cerium (PI–Ce) complex HFMs using a carboxylic group-containing 6FDA-mPDA0.65-DABA0.3-TFMB0.05 copolyimide through metal ion coordination to achieve plasticization-resistance helium recovery from natural gas. We optimized dope compositions and spinning conditions to produce defect-free hollow fiber membranes with a skin layer as thin as 300 nm. The coordination between carboxyl groups and cerium ions was characterized using Fourier Transform Infrared Spectroscopy (FTIR) and Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy. The polymer-metal coordinated membranes exhibited enhanced gas selectivities compared to the pristine HFMs due to the tailored microporosity achieved through polymer-metal coordination. Furthermore, the PI-Ce HFMs demonstrated only a 10.8 % decline in mixed-gas He/CH4 selectivity, which is significantly lower than the 55.4 % decline observed in pristine HFMs when exposed to CO2-containing feed pressures below 400 PSIA. Molecular dynamics simulations confirmed that coordination confined molecular chain swelling, thereby suppressing plasticization caused by CO2. The exceptional plasticization resistance of the PI-Ce complex HFMs provides a novel strategy for recovering helium from aggressive natural gas environments.

Metal-Coordinated, Dual-Crosslinked PIM Polymer Membranes for Upgraded CO2 Separation: Aging and Plasticization Resistance.

The practical use of polymers of intrinsic microporosity (PIMs) in CO2 separation is often hindered by their moderate selectivity, performance instability over time, and pressure constraints. To address these limitations, a straightforward approach is presented to enhance the CO2 separation capability of PIM-1 by incorporating metal ions into uniformly hydrolyzed PIM-1 (cPIM). This dual linking strategy, achieved via ionic and coordination bonding of metal ions with the polymeric side chains including ─COOH and ─CONH2, restructures the polymer, disrupting hydrogen bonds between cPIM chains and creating active sites for CO2 via π-complexation. This modification enhances gas permeability while maintaining high selectivity. The optimized zinc-coordinated membrane achieves an impressive CO2 permeability of ≈2,500 Barrer with CO2/N2 and CO2/CH4 selectivities of 27.1 and 23, respectively, outperforming pristine cPIM (700 Barrer; CO2/N2=27; CO2/CH4=19). Notably, this performance surpasses the 2008 Robeson upper-bound limits for both gas pairs. Additionally, the metal-coordinated membranes exhibit remarkable long-term stability, resisting aging effects for up to 20 days and maintaining anti-plasticization properties at pressures up to 20 bar. These dual-crosslinked membranes demonstrate promising potential for mixed gas separation, indicating their suitability for real-world industrial applications.

Impact Absorption Power of Polyolefin Fused Filament Fabrication 3D-Printed Sports Mouthguards: InVitro Study.

This study aims to evaluate and compare the impact absorption capacities of thermoformed ethylene vinyl acetate (EVA) mouthguards and 3D-printed polyolefin mouthguards used in sports dentistry applications. The objective is to determine whether 3D-printed polyolefin mouthguards offer superior impact toughness compared to traditional EVA mouthguards commonly used in sports settings. Six material samples were assessed: five pressure-formed EVA mouthguards (PolyShok, Buffalo Dental, Erkoflex, Proform, and Drufosoft) and one 3D-printed synthetic polymer (polyolefin). The materials were evaluated using a modified American Society for Testing and Materials (ASTM) D256 Test Method A for Izod pendulum impact resistance of plastics. Polyolefin samples were 3D-printed using fused filament fabrication (FFF) technology. Notably, the FFF process included samples printed with notches placed either parallel or perpendicular to the build direction. This orientation served as a study factor, allowing for comparison of material behavior under different printing conditions. Impact testing was conducted using an Izod impact tester to assess the materials' performance under controlled impact conditions. The study achieved a high power (1.0) in power analysis, indicating strong sensitivity to detect significant differences. Among molded materials, PolyShok showed significantly lower impact toughness compared to others (p = 0.06). The mean impact absorption of EVA materials was 5.4 ± 0.3 kJ/m2, significantly lower than polyolefin materials, which demonstrated 12.9 ± 0.7 kJ/m2 and superior performance (p = 0.0). Horizontal-notched polyolefin samples exhibited higher impact strength compared to vertical-notched samples (p = 0.009). 3D-printed polyolefin mouthguards exhibited significantly higher impact toughness than thermoformed EVA mouthguards. While EVA materials demonstrated structural robustness, their lower impact resistance and observed tearing in other test specimens suggest the need for alternative testing standards to better reflect real-world conditions. 3D-printed mouthguards fabricated with build orientations perpendicular to the direction of impact demonstrate significantly enhanced impact absorption. Further research into manufacturing methods and testing protocols is recommended to optimize mouthguard performance under impact scenarios.

Maleimide-induced crosslinking of polyimide membranes for high gas separation performance and plasticization resistance

Trade-off effect and plasticization are the key issues confronted in the area of membrane separation when dealing with applications involving high-pressure, soluble gases like CO2. In this study, a novel diamine (TAPA-MAA) was synthesized derived from tris(4-aminophenyl)amine (TAPA) and maleic anhydride (MA). This diamine was copolymerized with DAM (2,4,6-trimethylbenzene-1,3-diamine) and 6FDA (4,4′-(hexafluoroisopropylidene)diphthalic anhydride) to form the polyimide (PI) membrane containing maleimide (MI) cross-linking sites via chemical imidization way. Then, under the action of heat treatment, the crosslinked PI (cPI) membrane was constructed since the MI crosslinking initiates a radical cycloaddition reaction to form a succinimide-linked structure, and named as cPSI membrane for short. Further, an increase in the ratio of TAPA-MAA gives rise to the resultant cPSI membrane with elevated cross-linking density. The obtained cPSI membranes showed significantly enhanced gas selectivities and superior anti-plasticization property compared to the un-crosslinked PI membranes due to the MI-induced crosslinking reaction in the PI main chain, resulting in a marked increment (24 %) in ultra-microporosity (<7 Å) and a reduction in the d-spacing value (6.10 Å vs 5.80 Å), generating a strong molecular sieving effect. Meanwhile, the highly interconnected covalent structure formed by the MI-induced crosslinking will suppress the plasticizing phenomenon induced by high-pressure soluble gases. The typical membrane (cPSI-3:7-350) possessed great CO2/CH4 separation performance, CO2 permeability of 334.4barrer and a CO2/CH4 selectivity of 61.9 that is exceeded the 2008Roberson upper bound, along withCO2 plasticization pressures above 44 bar. Besides, its mixed CO2/CH4 separation performance exceeded the 2018 upper gas mixture limit when the upstream pressure changed from 2-20 bar. This study provides valuable insights for the design of PIs containing MI cross-linking sites, which can enhance the performance of membrane-based gas separation.

Effect of graphite on microstructure and friction-wear properties of yttria-stabilized zirconia coatings

Yttria-stabilized zirconia and flake graphite composite (C/YSZ) coatings were successfully prepared on a TC4 substrate by electrophoretic co-deposition and sintering at 1100 °C using YSZ nanopowder and flake graphite. The effects of the graphite content on the microstructure and friction-wear properties were investigated. The results indicated that flake graphite agglomerated in the C/YSZ coating. The YSZ coating with 0.6wt.% graphite exhibited the highest toughness with the plastic resistance index (H/E) of 0.0172, which was 6.8 % higher than that of the YSZ coating, and effectively inhibited the formation of coating cracks. However, an increase or a decrease in the graphite content led to a decrease in the toughness of the C/YSZ composite coating. The agglomerated graphite in the C/YSZ composite coating acted as a solid lubricant and affected friction and wear properties. The coefficient of friction (COF) of the 0.6C/YSZ sample was 0.45, which was 40 % lower than that of the YSZ sample. The reason for this was that graphite effectively inhibited the falling-off of debris from the coating surface and reduced abrasive wear. However, an excessive amount of graphite, i.e., in case of the 0.8C/YSZ coating, decreased the roughness of the wear surface, leading to a reduction in the H/E and COF by 24.4 % and 29.7 %, respectively.

Flexural response of metallurgically bonded steel-aluminium foam-steel panels and composite beams

This paper presents the results of an experimental and numerical campaign aimed at investigating the flexural behaviour of both metallurgically bonded steel-aluminium foam-steel sandwich (MBSAFS) panels and steel-MBSAFS composite beams. Three-point bending tests were carried out and the obtained results were used to validate the accuracy of analytical models to predict the stiffness and resistance of both MBSAFS panels and the composite beams. The predictive capacity of the analytical equations was further verified against the results of parametric finite element simulations, which were also carried out to investigate the influence of the thickness of the steel sheet, the foam thickness, the strength of the materials, the span length, and the type of beam profile. The comparative analysis demonstrated that the predictive formulae accurately provide both stiffness and resistance. The stiffness was predicted with a mean ratio (analytical/FEM) equal to 1, accompanied by a coefficient of variation (CoV) equal to 0.02. The plastic resistance of the composite beam was predicted with a mean accuracy of 0.96 and a coefficient of variation of 0.01.

Targeting SWI/SNF ATPases reduces neuroblastoma cell plasticity.

Tumor cell heterogeneity defines therapy responsiveness in neuroblastoma (NB), a cancer derived from neural crest cells. NB consists of two primary subtypes: adrenergic and mesenchymal. Adrenergic traits predominate in NB tumors, while mesenchymal features becomes enriched post-chemotherapy or after relapse. The interconversion between these subtypes contributes to NB lineage plasticity, but the underlying mechanisms driving this phenotypic switching remain unclear. Here, we demonstrate that SWI/SNF chromatin remodeling complex ATPases are essential in establishing an mesenchymal gene-permissive chromatin state in adrenergic-type NB, facilitating lineage plasticity. Targeting SWI/SNF ATPases with SMARCA2/4 dual degraders effectively inhibits NB cell proliferation, invasion, and notably, cellular plasticity, thereby preventing chemotherapy resistance. Mechanistically, depletion of SWI/SNF ATPases compacts cis-regulatory elements, diminishes enhancer activity, and displaces core transcription factors (MYCN, HAND2, PHOX2B, and GATA3) from DNA, thereby suppressing transcriptional programs associated with plasticity. These findings underscore the pivotal role of SWI/SNF ATPases in driving intrinsic plasticity and therapy resistance in neuroblastoma, highlighting an epigenetic target for combinational treatments in this cancer.

In situ hydrolyzed microporous polymer membranes for additional free volume to facilitate CO2 permeation

Advancements in membrane separation technology play a pivotal role in separation processes closely associated with the environment and energy. However, presently available commercial polymeric membranes encounter the challenge of low permeability, impacting both separation efficiency and membrane module costs. Here, we propose a simple and effective in situ acid hydrolysis strategy to significantly enhance membrane permeability. Specifically, a tetrafluorinated monomer with hydrolyzable Schiff base groups (TFNAD) has been meticulously designed, synthesized, and copolymerized with commercial TFTPN and TTSBI, yielding a series of copolymers. Subsequently, in situ hydrolysis removes aniline from the membrane, freeing up the occupied free volume and creating additional channels for gas transport. This process substantially enhances gas permeability while preserving the desired selectivity. PIM-TFAD-30 showed a 68 % improvement in CO2 permeability with virtually no compromise in CO2/N2 selectivity compared to the pre-hydrolysis membrane. Meanwhile, PIM-TFAD-30 also displayed outstanding separation performance and plasticization resistance in simulated flue gas tests, demonstrating its potential for practical application. This facile and straightforward hydrolysis method opens up a new perspective for preparing and modifying polymeric separation membranes beyond gas separation.

Highly plasticization-resistant Tröger’s base polymer–MOF mixed-matrix membranes for stable gas separation

The plasticization phenomenon, characterized by polymer chain swelling when exposed to highly soluble gas at high feed pressure, has been a major problem for polymer membranes. To address this, we prepared Tröger’s base (TB) polymer-based metal–organic framework (MOF) mixed-matrix membranes (MMMs), which are highly plasticization-resistant membranes. Three different highly porous MOF nanoparticles (ZIF-8, UiO-66-NH2, and MIL-101(Cr)) were prepared in small particle sizes. The corresponding MMMs were formed with a 30 wt% MOF loading to study the effects of MOF species, particle size, chemical functionality, and MOF–polymer interfacial interaction on gas-transport properties and plasticization behavior. The TB polymer-based MOF MMMs exhibited significantly higher H2 and CO2 permeabilities (fourfold to eightfold) than the TB polymer membrane owing to the porous nature and high gas adsorption capacity of the MOF. Additionally, the TB-based MOF MMMs, particularly the UiO-66-NH2 MMM, displayed exceptional CO2 plasticization resistance. This is attributed to the interfacial interaction of the strong hydrogen bonding between the amine group of the TB polymer and the amino group of UiO-66-NH2, as confirmed by small-angle X-ray scattering characterization. This TB polymer-based MOF MMM approach provides a feasible and effective route for enhancing gas-transport properties and CO2 plasticization resistance to achieve energy-efficient and stable gas separation.

Experimental and Numerical Study on the Performance of Steel–Coarse Aggregate Reactive Powder Concrete Composite Beams with Uplift-Restricted and Slip-Permitted Connectors under Negative Bending Moment

An innovative form of steel–concrete composite beam, the steel–coarse aggregate reactive powder concrete (CA-RPC) composite beam with uplift-restricted and slip-permitted (URSP) connectors, is introduced in this paper. The aim is to enhance the cracking resistance under negative bending moments, which is a difficult problem for traditional composite beams, and to make the cost lower than using ordinary reactive powder concrete (RPC). An experimental investigation of the behavior of six specimens of simply supported steel–CA-RPC composite beams with URSP connectors under negative bending moments is presented in this paper. The test results validated that the cracking load of steel–CA-RPC composite beams could be approximately three times that of the ordinary steel–concrete composite beams while the bearing capacity and stiffness are almost the same. A numerical model, using the concrete damaged plasticity (CDP) model to simulate the behavior of the CA-RPC material, was proposed and successfully calculated the overall load–displacement relationship of the composite beams with sufficient accuracy compared with the experimental results, and the distribution of cracks and the failure mode of the beams could also be captured by this model. Furthermore, a parametric analysis was carried out to find out how the application of prestress, CA-RPC, and URSP connectors could affect the cracking resistance of the composite beams, and the results indicated that using CA-RPC and prestress made the main contributions and that the usage of URSP could boost the effect of the other two factors. The plastic resistance moment of the beams was also compared with the calculation results using the methods introduced in Eurocode 4, and it was proved that the calculation results were lower than the experimental results by approximately 10%, which meant that the method was reliable for this kind of composite beam.

Recent Progress in Ultrasonic Surface Rolling: A Comprehensive Overview

Metals and their alloys have found extensive applications in numerous fields. Various surface modification techniques have received significant attention for their potential to improve the adaptability of materials to complex environments. One such technique, the ultrasonic surface rolling process (USRP), introduces a deformation layer by applying static stress and dynamic impacts to the surface of metallic materials. During USRP treatment, remarkable beneficial compressive residual stresses (CRS) and hardened layers are induced and, simultaneously, the surface finish of the material is improved. These modifications not only effectively suppress the initiation and propagation of fatigue cracks but also significantly enhance the mechanical properties, wear, and corrosion resistance of the materials, thereby greatly prolonging the service life of structural components. The review starts with the mechanisms of USRP, discussing grain refinement, control of surface roughness, and the introduction of beneficial CRS. Subsequent sections provide a comprehensive analysis of how these modifications impact material properties, encompassing hardness, plasticity, fatigue, wear, and corrosion resistance. Furthermore, it introduces the latest advancements in USRP technology, including thermal/electric pulse‐assisted USRP, its integration with other surface treatment methods, and its applications and prospects across various fields.