Permeability Coefficient Research Articles

The evolution of fractures in deep, weakly cemented overlying strata and the characteristics of severe and mild fracture zones

Fracture development in the overlying strata of a quarry is a key factor leading to aquifer water loss. Clearly understanding the fracture characteristics of deeply weakly cemented overburden is of significant importance for water-preserved mining. In order to investigate further the laws governing fracture evolution and zoning characteristics of deep, weakly cemented overlying strata, research methods, including theoretical analysis, numerical simulation, and engineering measurement, are employed. The calculation method of seepage velocity is derived by using the formula for the vertical permeability coefficient of the mining aquiclude. Based on the relationship between the seepage velocity of the aquiclude and the recharge velocity of the overlying aquifer under critical water conservation conditions, a quantitative formula characterizing the water-blocking capacity of the aquiclude is proposed. It is found that the variation in permeability of the aquiclude is negatively correlated with the distance from the working face. Consequently, the fracture zoning characteristics of deeply weakly cemented overburden rock, centered around the water-blocking capacity of fractured rock strata, are summarized. The simulation analysis of the evolution of fractures in overlying rock reveals that the compaction range of fractures increases as the working face lengthens. However, the overall development range of fractures remains largely unchanged. Additionally, the expansion of the tensile fracture range occurs solely in the vertical direction as mining height increases, while the compaction range of fractures gradually diminishes. Microseismic monitoring indicates higher incidences of fractures in the structural equilibrium zone and severe fracture zone, with more frequent occurrences of tensile and shear failures. Conversely, the mild fracture zone exhibits fewer occurrences of fractures.

Theory-based cryopreservation mode of mesenchymal stromal cell spheroids

Cryopreservation of spheroids requires development of new improved methods. The plasma membranes permeability coefficients for water and cryoprotectants determine time characteristics of mass transfer through the cell membranes, and therefore the optimal modes of cells cryopreservation. Here we proposed an approach to cryopreservation of multicellular spheroids which considers their generalised characteristics as analogues of the membranes' permeability coefficients of the individual cells. We have determined such integral characteristics of spheroids from mesenchymal stromal cells (MSCs) as osmotically inactive volume; permeability coefficients for water and Me2SO molecules and the activation energy of their penetration. Based on these characteristics, we calculated the osmotic behaviour of multicellular spheroids under cooling conditions to select the optimal cooling rate. We also determined the optimal cooling rate of spheroids using the probabilistic model developed based on the two-factor theory of cryodamage. From the calculation it follows that the optimal cooling rate of the MSC-based spheroids is 0.75 °С/min. To verify the obtained theoretical estimates, we conducted experiments on freezing MSC-based spheroids under different modes. The obtained results of primary viability screening indicate that freezing at a constant linear cooling rate of 0.75 - 1.0 °С/min gives a good result. Theoretical prediction of the spheroid osmotic behaviour during cooling provided the basis for experimental verification of varying the temperature to which slow cooling should be carried out before immersion in liquid nitrogen. Slow freezing of spheroids to -40 °C followed by immersion in liquid nitrogen was shown to preserve cells better than slow freezing to -80 °C. Obtained data allow more effective use of MSC-based spheroids in drug screening and regenerative medicine.

Properties and Microstructure of a Cement-Based Capillary Crystalline Waterproofing Grouting Material

Cement grout is traditionally used for treating water leakage distress in tunnels. However, traditional cement grout has the disadvantages of a poor anti-seepage performance, long setting time, and slow strength gain. To this end, a high-performance cement-based capillary crystalline waterproofing (CCCW) grouting material was synthesized using cement, capillary crystalline material, and several admixtures. The influences of the material proportions on the viscosity, bleeding rate, and setting time of the fresh grout, as well as the permeability coefficient of the grouted aggregate and the unconfined compression strength of the hardened grout material, were systematically studied. The mineralogy and microstructure of the CCCW grouting material were examined using X-ray diffraction, industrial computed tomography, and scanning electron microscopy. The results indicated that the capillary crystalline material PNC803 was not suitable for mixing with bentonite, sodium chloride, and triethanolamine in cementitious slurries, but it can produce excellent synergistic effects with sulfate, calcium chloride, and triisopropanolamine. An analysis of the microstructure of the CCCW grouting material showed that the PNC803 and additives can promote the hydration of cement, which yields more hydration products, sealing water passage and filling micro voids and therefore leading to enhanced waterproofing and strengthening effects. These research results could improve the applicability of CCCW material in tunnel engineering.

Thrombin generation, fibrin clot permeation and lysis in patients with severe mitral regurgitation undergoing transcatheter edge-to-edge mitral valve repair: Mitral Fibrin Study.

The intricate management of heart failure (HF), especially in the context of reduced ejection fraction, is compounded by an elevated risk of thromboembolic events. Existing studies offer inconclusive insights into the interplay between MR and the coagulation system. This study aimed to investigate the impact of transcatheter edge-to-edge repair (TEER) on specific coagulation parameters in HF patients. A cohort of 31 HF patients with severe MR undergoing TEER underwent systematic evaluation at three time points (V1, V2, and V3). Coagulation parameters, including fibrinogen concentration, thrombin generation, fibrin clot permeability (Ks), and clot lysis time (CLT), were assessed (n = 27 [V2], and n = 25 [V3]). TEER induced changes in fibrinogen levels (P = 0.01, V3 vs. V2) and improved fibrin clot properties over a 50-day follow-up (Ks, P = 0.01, V3 vs. V2). No significant differences were observed among time points in analyzed blood clot parameters. Correlation analysis showed that baseline CLT was significantly associated with delta NT-proBNP, (P = 0.049; r = 0.40). Multivariable analysis demonstrated that baseline CLT was an independent predictor of the early post-TEER NT-proBNP change (R2 = 0.55, P = 0.02). We found that fibrinogen levels decreased, and permeation coefficient increased over a median 50-day post-TEER follow-up, compared to early post-procedure assessments. Other blood coagulation parameters remained unchanged from baseline to both follow-up periods after TEER. Finally, CLT was an independent predictor of early NT-proBNP increase, emphasizing its role as an indicator of the hemodynamic response to TEER.

Study on Permeability Evolution Law of Rock Mass under Mining Stress

In order to study the stress–strain–permeability coefficient relationship of overlying strata in a fractured zone after coal mining, taking the Changcun coal mine in the Changzhi basin as an example, the permeability evolution law of coarse sandstone, fine sandstone, siltstone and mudstone during a stress–strain process was analyzed through a triaxial compression permeability test. The generalized model of the rock mass permeability evolution process under mining stress was summarized, and then a coupling model of the stress–water pressure–permeability coefficient of fractured rock was established based on the continuum model of rock mass. The results showed that the maximum permeability coefficient of different coal overburden types was quite different, and the peak strength of the rock mass preceded the maximum permeability coefficient during the rock mass failure process; the permeability coefficient first decreased and then increased, reaching its maximum value after the peak stress, which occurred during the strain-softening stage; the generalized model of rock mass permeability included the compaction stage, elasticity stage, stable fracture stage, unstable fracture stage, macroscopic failure stage and residual strength stage.

Analysis of three-dimensional slope stability combined with rainfall and earthquake

Abstract. In the current context of global climate change, geohazards such as earthquakes and extreme rainfall pose a serious threat to regional stability. We investigate a three-dimensional (3D) slope dynamic model under earthquake action, derive the calculation of seepage force and the normal stress expression of slip surface under seepage and earthquake, and propose a rigorous overall analysis method to solve the safety factor of slopes subjected to combined with rainfall and earthquake. The accuracy and reliability of the method is verified by two classical examples. Finally, the effects of soil permeability coefficient, porosity, and saturation on slope stability under rainfall in a project located in the Three Gorges Reservoir area are analyzed. The safety evolution of the slope combined with both rainfall and earthquake is also studied. The results indicate that porosity has a greater impact on the safety factor under rainfall conditions, while the influence of permeability coefficient and saturation is relatively small. With the increase of horizontal seismic coefficient, the safety factor of the slope decreases significantly. The influence of earthquake on slope stability is significantly greater than that of rainfall. The corresponding safety factor when the vertical seismic action is vertically downward is smaller than that when it is vertically upward. When considering both horizontal and vertical seismic effects, slope stability is lower.

Integrated geophysical and geochemical characterization of hydrocarbon contaminated site in Erhoike-Kokori, Southern Nigeria

The effectiveness of geophysical and geochemical methods in delineating hydrocarbon contamination in a spill site is carried out around theErhoike flow station in Kokori, Ethiope East LGA, Delta State. Wenner array was used for the transverse in acquiring the data which spanned a transverse of 200m and 3D model resistivity images were obtained from the inversion and presented in horizontal depth slices. Well water samples were also taken for Total Petroleum Hydrocarbon (TPH) content while soil samples from the location were also taken for Porosity and coefficient of permeability. The result of the 3D horizontal depth slices in the location reveals that Erhoike is impacted with hydrocarbon plume to a depth of 31.7m. The concentration of TPHCs from the water analysis shows that the wells around the suspected zones are affected by hydrocarbon. The laboratory tests for porosity (Փ ) and coefficient of permeability (k) for the soil samples are indicative of sand/silty sand which thus allows the flow of PHCs plume to the soil and groundwater in the study area. The results of the study have shown that the soil is permeable and porous which would allow the passage of the leaked and spilled PHCs through the soil to groundwater where the PHCs could mix, float and sink into groundwater. The 3D analysis revealed the presence of PHCs up to a depth of 33.7m but prominent at a depth of 10m which indicates the presence of PHCs in the wells. The hydrochemical analysis also proved the same results as that of the 3D which authenticated the reliability of the method used in the study.

Reusable and effective polyacrylic membranes for mecoprop and bentazon extractions

This study introduces reusable polyacrylic membranes, fabricated from commercially available monomers (1-vinyl-2-pyrrolidone and methylmethacrylate), as a promising approach for pesticide extraction. These membranes effectively remove the commonly used herbicides mecoprop (RE ≈ 99%) and bentazon (RE ≈ 95%) at low concentrations, which pose water contamination risks due to their water-soluble properties and leaf-level sorption. The membranes exhibit excellent manageability and resistance, allowing for safe handling without personal protective equipment. Additionally, the material is environmentally friendly and can be washed and reused for at least 4 cycles without a significant decrease in performance. Characterization techniques, including NMR, TGA, DSC, mechanical testing, N2 adsorption, and FTIR analysis, were used to investigate properties and assess the influence of the polymeric composition. The study focused on examining the lateral charged aminoethyl groups, which play a crucial role in sorbent-sorbate interactions. Sorption kinetics, isotherms, and permeation studies provided insights into the removal mechanism, efficiency, and permeability coefficients, revealing hydrophobic–hydrophobic interactions between the pesticides and the polymer. Molecular dynamics simulations revealed a scorpion-like conformation of the macromolecular chains surrounding the pesticides. These findings support the hydrophobic nature of the extraction mechanism and highlight the significant role of charged aminoethyl groups in facilitating this process.

Propellant Free Pressurized Spray System of Etodolac to Manage Acute Pain Conditions: In Vitro and In Vivo Evaluation.

This study aimed to develop a propellant-free topical spray formulation of Etodolac (BCS-II), a potent NSAID, which could be beneficial in the medical field for the effective treatment of pain and inflammation conditions. The developed novel propellant-free spray formulation is user-friendly, cost-effective, propellant-free, eco-friendly, enhances the penetration of Etodolac through the skin, and has a quick onset of action.Various formulations were developed by adjusting the concentrations of different components, including lecithin, buffering agents, film-forming agents, plasticizers, and permeation enhancers. The prepared propellant-free spray formulations were then extensively characterized and evaluated through various in vitro, ex vivo, and in vivo parameters. The optimized formulation exhibits an average shot weight of 0.24 ± 0.30ml and an average drug content or content uniformity of 87.3 ± 1.01% per spray. Additionally, the optimized formulation exhibits an evaporation time of 3 ± 0.24min. The skin permeation study demonstrated that the permeability coefficients of the optimized spray formulation were 21.42cm/h for rat skin, 13.64cm/h for mice skin, and 18.97cm/h for the Strat-M membrane. When assessing its potential for drug deposition using rat skin, mice skin, and the Strat-M membrane, the enhancement ratios for the optimized formulation were 1.88, 2.46, and 1.92, respectively against pure drug solution. The findings from our study suggest that the propellant-free Etodolac spray is a reliable and safe topical formulation. It demonstrates enhanced skin deposition, and improved effectiveness, and is free from any skin irritation concerns.

Study on the variation of the permeability coefficient of soil–rock mixtures in fault zones under different stress states

Study on the variation of the permeability coefficient of soil–rock mixtures in fault zones under different stress states

Experimental study on mechanical and hydraulic properties of xanthan gum improved low liquid limit silty soil

The low liquid limit silty soil in the North China plain area is generally unsuitable for direct use as roadbed and slope soil. In order to improve the performance of low liquid limit silty soil, xanthan gum was used as an improver. Through a series of tests, the improvement effect of xanthan gum on low liquid limit silty soil was studied. The test results showed that Xanthan gum as an improver could significantly improve the unconfined compressive strength of silty soil. With the increase in dosage and curing age, the unconfined compressive strength of improved silty soil continued to improve and eventually tended to stabilize. The optimal dosage and curing period were 2% and 7 days, respectively. In addition, Xanthan gum could greatly improve the permeability and disintegration of low liquid limit silty soil. The permeability coefficient of improved silty soil with a content of 0.75% Xanthan gum and a 7-day curing period was 4.73 × 10−4 m·s−1, which was only 1.10% of that of plain silty soil at the same curing period. After immersion in water for 12 h, the soil only experienced slight disintegration. The scanning electron microscope image showed that the gel generated by the hydration reaction of Xanthan gum could improve the compactness and integrity of the soil by filling the voids, thus significantly improving the mechanical and hydraulic properties of the low liquid limit silty soil.

Analysis of time-dependent bearing capacity of pile foundation in marine soft soil region considering non-Darcy flow

Due to the deviation of pore water seepage in marine soft soils from Darcy flow under low hydraulic gradients, existing methods face challenges in accurately calculating the time-dependent bearing capacity of piles in such areas. This paper adopts the secondary development of Python to ABAQUS and employs a continuous coupling analysis method to establish a numerical model capable of simultaneously solving the large deformation of pile driving and non-Darcy flow. The model addresses issues such as mesh distortion during pile driving and the numerical implementation of three-dimensional non-Darcy flow. The accuracy of the model was verified through comparison with two experimental cases. Subsequently, the study analyzed how non-Darcy flow affects soil consolidation around the pile and the time-dependent bearing capacity of pile. Results indicate that when the permeability coefficient of the soil around the pile is less than 1 × 10−7 m/s, non-Darcy flow significantly delays the consolidation of soil within three times the pile diameter around the pile, thereby reducing the time-dependent bearing capacity of pile, with a greater impact observed for lower permeability coefficients of the soil. Once the soil around the pile reaches 90% consolidation, subsequent construction can proceed to shorten the project duration while maintaining safety.

Compressive Strength, Permeability, and Abrasion Resistance of Pervious Concrete Incorporating Recycled Aggregate

Extensive use of cement in the construction industry increases CO2 emissions and has a negative impact on the environment. In this work, recycled coarse aggregate (RCA) from construction and demolition wastes (C&DW) was used to fabricate sustainable pervious concrete (PC). In order to mitigate the environmental hazards of excess cement waste and to improve the engineering properties of PC, silica fume (SF) and ground granulated blast-furnace slag (GGBS) were added. The effects of SF and GGBS on the compressive strength, permeability coefficient, porosity, and abrasion resistance of recycled aggregate pervious concrete (RAPC) were investigated. The results show that the incorporation of GGBS and SF effectively improves the compressive strength of RAPC but reduces the permeability coefficient and porosity. Moreover, due to the filling effect and pozzolanic activity, the incorporation of GGBS and SF significantly enhances the abrasion resistance of RAPC. Furthermore, the relationships between the compressive strength, permeability coefficient, porosity, and abrasion resistance of RAPC are clarified. The optimum replacement is achieved when the SF content is 7%, and the GGBS content is 20%, respectively, which results in the highest compressive strength (28.9 MPa) and the lowest permeability coefficient (1.2 mm/s) at 28 days, and the lowest mass loss rate (12.1%) after the Cantabro abrasion test.

A face-to-face comparison of the BBB cell models hCMEC/D3 and hBMEC for their applicability to adenoviral expression of transporters.

The blood-brain barrier (BBB) is a structure mainly formed by brain capillary endothelial cells (BCEC) whose role is to regulate the exchange of compounds between the blood and the brain. In this process efflux and uptake transporters play a key role. Aim of this study was to compare the two previously established cell lines hCMEC/D3 and hBMEC as BBB cell models for the application of an adenoviral system to transiently express OATP2B1 and Pgp. Comparison of hCMEC/D3 and hBMEC mRNA and protein levels of BBB markers showed a unique expression pattern for each cell line. While showing similar expression of the efflux transporter BCRP, transferrin receptor (TFRC) and of the tight junctions proteins Occludin and ZO-1, hCMEC/D3 displayed higher levels of the endothelial marker PECAM1, VE-cadherin, Von Willebrand Factor (VWF) and of the efflux transporter Pgp. Moreover, measuring integrity of the monolayer by determining the Trans-Endothelial Electrical Resistance (TEER), electrical capacitance (CCl), and inulin apparent permeability coefficient (Papp) revealed higher TEER and lower CCl for hBMEC but comparable Papp in the two cell lines. Following adenoviral infection, enhanced OATP2B1 and Pgp expression and functionality could be observed only in hBMEC. Importantly, the adenoviral expression system did not affect expression of BBB markers and permeability in both cell lines. Taken together, our results provide first evidence that hBMEC is an applicable human BBB cell model in which adenoviral infection can be used to transiently express and investigate transporters of interest.

Analysis of pipeline leakage in unsaturated stratum: A new seepage-diffusion model

Accurate prediction of the spread of fluids leaking from underground pipelines is crucial for risk assessment. In this study, we developed a method for predicting the diffusion range of pipeline seepage fluids within an unsaturated stratum. First, we derived a seepage–diffusion equation based on the generalized Darcy’s law and subsequently analyzed the mechanism of fluid diffusion in the unsaturated stratum. We then constructed a model for the seepage–diffusion of a pipeline leakage fluid, incorporating variables such as the saturation, permeability coefficient, diffusion pressure, and diffusion distance of soil microelements across various time intervals, using a stepwise algorithm in tandem with the Green–Ampt model and VG–Mualen permeability coefficient function. We investigated the influence of fluid self-gravity, saturated permeability coefficient, initial saturation, and intra-pipe pressure on the diffusion distance of the pipeline leakage fluid in an unsaturated stratum, focusing on specific cases. The results indicate that an increase in the saturated permeability coefficient, initial saturation, and intra-pipe pressure leads to an increase in the fluid diffusion distance. A simulation test was conducted to validate the proposed seepage–diffusion model. The findings of this study can be employed to predict the diffusion range of pipeline leakage fluids in various formation types, providing a vital foundation for pipeline leakage accident management.

Quantitative characterization of microstructure and research on spatial variation characteristics of loess of different strata in Luochuan, Shaanxi, China.

The complete sequence of loess strata in Luochuan has become a typical section in loess strata, and is the main focus of research for many scholars studying loess. We were based on the theory of aeolian loess and established a set of quantitative index parameters for loess microstructure through our previous research, such as equivalent diameter, sphericity, morphology ratio, orientation angle Phi, orientation angle Theta, pore Eq-Radius, throat Eq-Radius and throat channelLength. Through the quantitative characterization of various index parameters of the Luochuan loess, we found that the probability density of each index parameter meets a specific distribution well, and in terms of spatial dimension, it shows that as the depth of the strata increases, the average particle size and the mode of pore Eq-Radius, throat Eq-Radius and throat channelLength generally increase, while the mode of particle morphology ratio generally decreases. In addition, loess particles in deeper strata are less prone to vertical sedimentation and tend to deposit gently or horizontally. Most particles in different strata are distributed in a northwest or southwest direction. During the formation period of strata, the main cause for spatial differences is the material carrying force. We conducted a statistical analysis on the correlation between the macroscopic physical properties of loess and its microstructure index parameters. Specifically, we found a positive correlation between loess density and the average particle size and the mode of particle equivalent diameter, Additionally, we found a negative correlation between loess liquid limit and plastic limit, and the mode of particle morphology ratio. Furthermore, there was a negative correlation between permeability coefficient and the mode of pore Eq-Radius, throat Eq-Radius, and throat channelLength.

Inversion of the Permeability Coefficient of a High Core Wall Dam Based on a BP Neural Network and the Marine Predator Algorithm

The parameters’ inversion of saturated–unsaturated is important in ensuring the safety of earth dams; many scholars have conducted some research regarding the inversion of hydraulic conductivity based on seepage pressure monitoring data. The van Genuchten model is widely used in saturated–unsaturated seepage analysis, which considers the permeability connected to the water content of the soil and the soil’s shape parameters. A BP neural artificial network is a mature prediction technique based on enough data, and the marine predator algorithm is a new nature-inspired metaheuristic inspired by the movement of animals in the ocean. The BP neural artificial network and marine predator algorithm are applied in the permeability coefficient inversion of a core-rock dam in China; the results show that in the normal operation status, the BP network shows better accuracy, and the average of the absolute error and variance of the absolute error are both minimum values, which are 2.21 m and 1.43 m, respectively. While the water storage speed changes, the marine predator algorithm shows better accuracy; the objective function is calculated to be 0.253. So, the marine predator algorithm is able to accurately reverse the desired results in some situations. According to the actual condition, employing suitable methods for the inverse permeability coefficient of a dam can effectively ensure the safe operation of dams.

Development of high barrier poly(l-actic acid)/chitosan/graphene oxide flexible films for meat packaging by layer-by-layer

An new high-barrier packaging films for meat preservation were obtained by depositing graphene oxide (GO) layer-by-layer (LbL) on poly(l-lactic acid)(PLLA)-poly (butylene itaconate) (PBI) copolymers (PLBI) with chitosan (CS) as bonding layer in this study. The 1H NMR results revealed that PLBI copolymer was successful synthesized. The introduction of PBI reduced the Tg and crystallization capacity of PLLA film, which made the copolymer films exhibit extremely high flexibility (up to 186.1% elongation at break). The film also exhibited high hydrophilicity, which was favorable for the effective attachment of CS. With CS as an intermediate layer, the FTIR and SEM results showed that the GO was evenly distributed onto the PLBI film surface due to the electrostatic interaction. The oxygen, water vapor and UV light barrier properties of PLBI/CS/(GO-CS)x films were improved and increased with the GO-CS layers. The PLBI/CS/(GO-CS)10 films, with extremely low oxygen permeability coefficients about 0.4 × 10−8 cm3 m/m2·h·Pa, delayed the increase in weight loss, hardness, pH, TVB-N, TBARS, and total viable counts of chilled meat during storage. It also decreased the discoloration, and loss of springness and cohesiveness of chilled meat caused by long-term refrigeration. The LbL films even showed better freshness-keeping effect than commercial PA/PE films due to its superior barrier and certain antibacterial properties, suggesting great potential application in fresh meat preservation.

Influence of field collected clogging material on the coefficient of permeability in porous asphalt mixture

Influence of field collected clogging material on the coefficient of permeability in porous asphalt mixture

Synergistic effect of combining UiO-66 nanoparticles and MXene nanosheets in Pebax mixed-matrix membranes for CO2 capture

The use of membrane-based gas separation has garnered significant interest owing to its cost-effectiveness, outstanding performance and positive environmental impact. The performance of gas separation membranes can be considerably enhanced by mixed-matrix membranes (MMMs), but poor interactions between additives and membrane matrix and the agglomeration of highly incorporated fillers in MMMs limit the benefits of overcoming tradeoff effect. Therefore, the regulation of the state of fillers in membrane matrix is a crucial indicator in the development of MMMs. In this study, MXene (Ti3C2Tx) nanosheets and UiO-66 nanoparticles were prepared and used as fillers, in combination with a Pepax-1657 matrix, to synthesize MMMs for CO2-gas separation. As-prepared MMMs were used for the separation; the large pores (0.5–0.6 nm) of UiO-66 served as a highway to enhance CO2 permeability, and MXene nanosheets were used as selective channels to achieve high selectivity via the terminal polar surface groups of MXene. The combination of UiO-66 and MXene not only enhanced the selectivity, but also increased the solubility and diffusivity via selective CO2 adsorption and the tortuous pathway provided by MXene nanosheets. As a result, adding MXene and UiO-66 to Pebax helped MMMs overcome the tradeoff effect. MMMs loaded with 10 wt% MXene/UiO-66 exhibited a CO2 permeability coefficient of 214.6 Barrer and an ideal CO2/N2 selectivity coefficient of 102. Dual filler-containing MMMs showed enhanced CO2 permeability coefficient and CO2/N2 selectivity in comparison to pristine Pebax and individual nanofiller-added membranes. In this study, the combination of 2D MXene and UiO-66 nanoparticles exerted a synergistic effect in improving the CO2 separation efficiency of MMMs. This research provides a novel route for fabricating high-performance MMMs in the separation of CO2.