Uniform Pore Distribution Research Articles

Bioactive fluorcanasite reinforced magnesium alloy based porous bio-nanocomposite bone scaffold with controlled degradation

ABSTRACT This study deals with the fabrication of magnesium-alloy-based biodegradable porous bone scaffolds. Selected amounts of calcium, zinc and strontium were incorporated into magnesium-metal-matrix as alloying elements to tune the degradation behaviour, while bioactive fluorcanasite nano-particulates were incorporated to promote bone growth. Green compacts with urea porogen were fabricated using the powder metallurgy route, followed by sintering to achieve the desired porosity in the fabricated samples. The microstructure of the fabricated samples was examined by FE-SEM, coupled with EDS, which revealed uniform distribution of pores and alloying elements. Degradation study of the fabricated bio-nanocomposites revealed the retardation of degradation rate, owing to the incorporation of alloying elements. Hydrogen evolution and pH studies of the immersed samples were also found to be in coherence with the degradation behaviour of the samples. These results, therefore, demonstrated that the fabricated magnesium alloy-based bio-nanocomposite scaffolds have promising potential for bone tissue engineering.

The efficacy of a paeoniflorin-sodium alginate-gelatin skin scaffold for the treatment of diabetic wound: An in vivo study in a rat model

ObjectiveTo investigate the efficacy of a paeoniflorin-sodium alginate (SA)-gelatin skin scaffold for treating diabetic wound in a rat model. MethodsBioinks were prepared using various percentages of paeoniflorin in the total weight of a solution containing SA and gelatin. Skin scaffolds containing 0%, 1%, 3%, 5%, and 10% paeoniflorin were printed using 3D bioprinting technology, and scaffold microstructure was observed with scanning electron microscopy. Skin scaffolds were then used in rats with diabetic wounds. H&E staining, Masson staining, and immunohistochemical staining for IL-1β and CD31 were performed on days 7 and 14. ResultsAll skin scaffolds had a mesh-like structure with uniform pore distribution. Wounds healed well in each group, with the 1% and 3% groups demonstrating the most complete healing. H&E staining showed that skin accessory organs had appeared in each group. On day 7, collagen deposition in the 3% group was higher than in the other groups (P＜0.05), and IL-1β infiltration was lower in the 10% group than in the 3% group (P = 0.002). On day 14, IL-1β infiltration was not significantly different between the 10% and 3% groups (P = 0.078). The CD31 level was higher in the 3% group than in the other groups on days 7 and 14 (P＜0.05). ConclusionA 3% paeoniflorin-SA-gelatin skin scaffold promoted the healing of diabetic wounds in rats. This scaffold promoted collagen deposition and microvascular regeneration and demonstrated anti-inflammatory properties, suggesting that this scaffold type could be used to treat diabetic wounds.

Design and analysis of the mechanical properties of controllable porous scaffolds for bone tissue engineering.

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Highly efficient catalytic derived synthesis process of carbon aerogel for hydrogen storage application

For the present work, resorcinol-formaldehyde (R–F) aerogels were synthesized through both acid (nitric acid) and base (sodium carbonate) catalyzed sol-gel process followed by supercritical drying (SCD) as well as ambient pressure drying (APD). RF aerogels were carbonized at high temperatures to form carbon aerogels. The effect of the catalyst type and drying methods on the final characteristics were studied in detail. Microstructural and textural characteristics were evaluated through XRD, SEM, BET, RAMAN, FTIR, and TEM techniques. It was found that the combination of base catalysis and SCD delivered a higher micropore density and more uniform pore distribution. The CAs prepared under such conditions displayed a hydrogen uptake of 0.80 wt% at room temperature and 2.85 wt% at liquid nitrogen temperature (77 K).

Preparation and evaluation of a silk fibroin-polycaprolactone biodegradable biomimetic tracheal scaffold.

In tracheal tissue engineering, the construction of tracheal scaffolds with adequate biodegradable mechanical capacity and biological functions that mimic the structure of a natural trachea is challenging. To explore the feasibility of preparing biomimetic degradable scaffolds with C-type cartilage rings and an inner tracheal wall of polycaprolactone and silk fibroin. A mold was made according to the diameter of a rabbit trachea, and a silk fibroin tube and polycaprolactone ring attached to the tube were obtained by solution casting. The ring was fixed to the tube at a specific spacing using electrostatic spinning technology to construct a biomimetic tracheal scaffold; its porous structure was observed by scanning electron microscopy, its degradation properties were determined by in vitro enzymatic hydrolysis and its mechanical properties were obtained by pressure testing. The composite scaffold was transplanted subcutaneously into a rabbit model, and the scaffold was taken at 1, 2, and 4 weeks after surgery for sectioning to observe pre-vascularization. The Medical Ethics Committee of Guangdong Provincial People's Hospital approved the study. The general view of the biomimetic scaffold: the polycaprolactone ring was fixed firmly on the outer wall of the silk fibroin tube; the two corresponded in size, and they fitted closely. The surface of the polycaprolactone ring was smooth and dense, while the surface of the silk fibroin tube could be seen as a uniform porous structure. Scanning electron microscopy showed that the surface and profile of the fibroin tube had a uniform pore size and distribution. The pores were connected to form a network. In vitro, enzymatic hydrolysis experiments confirmed that the fibroin was degraded easily, with most being degraded at the end of week 1. The degradation slowed at 2, 3, and 4 weeks, while the degradation of polycaprolactone was extremely slow. A compression test showed that the compressive resistance of the silk fibroin-polycaprolactone biomimetic scaffolds was much better than that of the rabbit trachea at close thickness. In the tissue staining experiments, as the material degraded, fibrous tissues and blood vessels grew to replace the material, allowing the scaffold to obtain a blood supply and better mechanical properties. A quantitative analysis of CD31 showed that the results for the vascularization of the scaffold were better at 4 weeks than at 2 weeks following subcutaneous grafting (P < .05). The results confirmed that it is feasible to prepare porous, degradable silk fibroin-polycaprolactone biomimetic scaffolds with good mechanical properties and epithelial biological functions by mold casting.

Adsorption Characteristics and Molecular Simulation of Malachite Green onto Modified Distillers’ Grains

Adsorbent material was prepared using distillers’ grains (DG), which is a waste product of distilleries. The DG was pre-treated with NaOH and esterification-modified with CS2, which is a commonly used anionic modifier. The structure and morphology of the adsorbent was characterized by FTIR, XRD, EDS, SEM, BET, and zeta potential. The related mechanism of adsorption of malachite green (MG) onto modified distiller’s grains (MDG) was studied by adsorption experiments and molecular simulation techniques. The experimental results showed that CS2 successfully modified the DG fiber, and simultaneously yielded the MDG with a uniform pore distribution. MDG had a considerable adsorption capacity of 367.39 mg/g and a maximum removal rate of 96.51%. After eight adsorption–desorption cycle experiments, the adsorption removal rate of MDG to MG dye remained at 82.6%. The adsorption process could be fitted well by a pseudo-second-order kinetic model (the correlation coefficient R2 &gt; 0.998) and Freundlich isotherm adsorption equation (the correlation coefficient R2 &gt; 0.972). Moreover, the adsorption of MG dye by MDG is a spontaneous, endothermic, and increased entropy process. The results of molecular simulation showed that the mechanism of MG molecules onto MDG was mainly chemical adsorption. The adsorption performance of MG onto MDG was better and more stable than DG. Molecular simulation also provided a theoretical guidance of MDG adsorption–desorption for the research on recycling of DG resources.

Effect of clay addition to Al2O3-agar mixture on pore size and distribution of tubular Al2O3 membrane support fabricated byagar gelcasting

The addition of clay particles— kaolin or bentonite—into the mixture of Al2O3 slurry and agar solution was examined for creating pores with controllable size in tubular Al2O3 membrane. The mixtures were prepared and then molded out of glass tubes using the method of agar gelcasting. The green, gelcast Al2O3 tubes were sintered at 1350 °C for 1 h for membrane application. The effect of clay addition from 0 to 2 wt% into the mixture on pore size and structure of Al2O3 tubes was observed with SEM. The addition of bentonite provided less uniform pore size and distribution than that of kaolin. Additionally, the step of ball milling the clay particles to make complete dispersion prior to adding to the mixtures was needed to create more uniform pore size and distribution. The ball milling time of 60 min was the optimum condition for preparing Al2O3 membrane support.

Fabrication and characterization of FITC-modified naturalbased silica nanoparticles using sol-gel method

This research aimed to synthesize fluorescent silica nanoparticles (SiFITC) modified with the fluorescein isothiocyanate (FITC) dye using sol-gel method. The FITC dye was used as the fluorophore to produce fluorescent silica nanoparticles. The precipitate from geothermal power plant containing SiO2 was used as a precursor and added with NaOH at 90°C generating sodium silicate. FITC solution was added with various concentrations ranging from 0.1, 0.2, 1, 5 to 10 mg/mL and the mixture was allowed to age for 18 hours. Characterization of SiFITC was measured using fluorescence spectrophotometer to obtain the fluorescence intensity, Fourier Transform Infra-Red (FT-IR) spectroscopy to determine the functional group of SiFITC, Brauner Emmett-Teller (BET) adsorption method to calculate the specific area of the nanoparticles, and X-ray diffraction (XRD) to analyze the crystallographic phases. Fluorescent intensity showed that SiFITC with 1 mg/mL of FITC had the lowest fluorescence intensity indicating self-quenching mechanism due to the overloading of the dye in the silica matrix. The FT-IR spectra showed vibration at wavenumber of 956 (Si-O); 1073 and 798 (Si-O-Si); 3396 (OH) and 1631 cm−1 (Si-OH). BET analysis showed that the specific surface of the SiFITC 480 m2/g and XRD results showed that the samples were in amorphous phase with uniform pore distribution. The results showed that the FITC-modified silica nanoparticles have great potential for further investigation in biosensing applications, particularly fluorescence or optical based detection of antibiotic resistant bacteria.

Behavior and mechanism of the adsorption of lead by an eco-friendly porous double-network hydrogel derived from keratin

In this study, a novel eco-friendly porous double-network keratin/polyacrylic acid (keratin-PAA) hydrogel was prepared using the one-pot method to improve the adsorption performance of the hydrogel toward Pb(II). The obtained porous keratin-PAA hydrogel was then characterized using nitrogen adsorption–desorption isotherms, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The interaction mechanism of Pb(II) and the keratin-PAA hydrogel was further investigated using X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The results showed that keratin-PAA hydrogel was successfully synthesized, with a specific surface area of 49.35 m2/g and a uniform pore distribution of 6.20 nm. The synthesized keratin-PAA hydrogel only took 6 min to adsorb nearly 70% of Pb(II) from the solution because of the interconnected porous network. The keratin-PAA hydrogel also showed a maximal adsorption amount of 234.6 mg/g, and satisfactory selectivity toward Pb(II). The adsorption kinetics of the keratin-PAA hydrogel binding to Pb(II) could be better described by the pseudo-second-order model, whereas the adsorption isotherms could be fitted using the Langmuir equation; this suggested that chemisorption was the main rate-limiting step. The XPS and FT-IR analysis results indicated that the sulfur-, nitrogen- and oxygen-containing groups in the keratin-PAA hydrogel were the main binding sites for Pb(II). In real aqueous samples, the keratin-PAA hydrogel could remove 93–104% of Pb(II). It is clear that the keratin-PAA hydrogel is an outstanding adsorbent material for the removal of Pb(II) from aqueous samples.

Investigating intra-aggregate microstructure characteristics and influencing factors of six soil types along a climatic gradient

Pore structure can reflect the soil aggregation process, determine various physical, chemical and biological processes in aggregates. This study investigates variations in the intra-aggregate microstructure (porosity, pore size distribution, and pore shape) of six different weathered soils across temperate (Haplic Phaeozems, HP; Haplic Luvisols, HL; Calcic Luvisols, CL), subtropical (Ferric Luvisols, FL; Plinthic Alisols, PA) and tropical (Acric Ferralsols, AF) climates. For this purpose, the three-dimensional microstructure of the soil aggregates using X-ray micro-computed tomography was quantified. Significant differences were found in the intra-aggregate microstructure of different soil types. The porosity of different effective pore diameters inside soil aggregates showed a U-shaped pattern of change, which gradually weakened with the increase in soil profile depth. HL, PA, and AF had higher total porosity and pore number, with a more uniform pore distribution, due to high content of SOC (soil organic carbon) or Fe–Al oxides. Large and long-shaped pores were found in the intra-aggregates of FL. The dominant soil intra-aggregate pores were mesopores (the porosity of effective pore size between 30 and 75 µm, P30-75) and the soil aggregate microstructure exhibited an elongated pore morphology. SOC and Al oxides were two determinants of the intra-aggregate microstructure with a significant positive effect, whereas Fe oxides’ negative effect was observed. These results have shed light on the main reasons for the differences in the microstructure of different weathered zonal soil intra-aggregates and the relationship between aggregate microstructure and cementing substances.

Numerical simulation for nanofluid extravasation from a vertical segment of a cylindrical vessel into the surrounding tissue at the microscale

Heat transfer in the biological tissue during/after thermal therapy is dominated by the blood perfusion in the tissue. In this study we introduce a mathematical model to simulate the heat and nanoparticle transport in the tissue in the presence of a vertical vessel at the microscale. This model incorporates the effects of the nanoparticle Brownian motion, nanoparticle transport due to thermophoresis and heat transfer by radiation. We consider the nanoparticles and the interstitial fluid extravasate from the vessel into the surrounding tissue through a uniform distribution of pores at the vessel wall . We introduce similarity transformations to convert the governing equations into a system of ODEs, which we solve numerically using MATLAB. The model predictions show a significant influence of the vessel pore size on the heat transfer in the tissue. On the other hand, the nanoparticle transport across the tissue depends on the thermophoresis parameter. Furthermore, the heat removal from the tissue by the vessel strongly depends on the fluid extravasation velocity and the heat flux across the tissue outer boundary interface.

Effects of Clay Mineral Composition on the Dynamic Properties and Fabric of Artificial Marine Clay

Marine clays are easily affected by different mineral composition in cyclic load-based geological hazards. Therefore, based on analyzing the mineral composition of natural marine clay, it is the key to predict the dynamic properties of natural materials under cyclic loading by using quantitated artificial marine clay. In this study, the marine clay found in the South China Sea deltas was investigated. Based on the results of geological conditions and mineral composition analyses, raw non-clay minerals (such as quartz, albite) and clay minerals (such as Na-montmorillonite and kaolinite) were used to produce artificial marine clay, the dynamic properties of which were studied from the impact of mineral composition. Dynamic triaxial laboratory testing for artificial marine clay comprising various clay minerals was performed under identical test conditions. The artificial marine clay with high montmorillonite content exhibited slower development of strain, more sluggish growth in pore water pressure, more rounded hysteresis curves, greater stiffness, and more prolonged viscous energy growth than the clay with low montmorillonite content. In addition, the flocculated fabric of the artificial marine clay with high montmorillonite content demonstrated sufficient pore space changes, more uniform pore distribution, and larger specific surface area than the dispersed fabric of the clay with low montmorillonite content. The factors arising from the influence of montmorillonite may lead to microstructural and fabric changes, hinder the development of pore water, and increase intergranular contact stiffness as well as delay the cyclic strain amplitude at the breakpoint of viscous energy dissipation. In general, the results presented in this study confirm that clay minerals, especially montmorillonite, have significant influence on the dynamic properties of large strain.

Preparation and characterization of red mud based porous materials

China was a large country in bauxite mining and refining. One ton of alumina was produced, accompanied by 0.5 ~ 2 tons of red mud [1]. Therefore, the accumulation and pollution of red mud had been a difficult problem to be solved by enterprises and local governments. In this paper, red mud based porous materials were prepared with Bayer red mud, perlite, silicon carbide (as foaming agent) and glass powder (as flux). The effects of sintering process and iron oxide on thermal conductivity, bulk density, porosity and compressive strength of red mud based porous materials were studied by TG-DSC, XRD, SEM and XEDS. The results show that red mud based porous materials with uniform pore distribution could be obtained when the amount of red mud was 60%, perlite was 37%, SiC was 1%, glass powder was 2%, sintering temperature was 1150 °C and holding time was 120 min. The true porosity of the red mud based porous material was 70%, and the average pore diameter was 216.84 μ m. The thermal conductivity was 0.26w / (m • K) and the compressive strength was 2.31MPa.

Bioactivity and biocompatibility of porous gradient bioceramic coating prepared via laser cladding process

In this work, porous gradient bioceramic coating was fabricated via laser cladding process, and its bioactivity and biocompatibility were evaluated by various tests such as simulated body fluid (SBF) soaking, cell proliferation, cell fixation, osteoblast staining, osteoblast alkaline phosphatase (ALP) activity, and hydroxyproline (HYP) activity. Various porous bioceramic coatings were prepared with 0, 2.5, 5, 7.5, and 10wt% forming agents, and they were denoted as 0 wt% PFA, 2.5 wt% PFA, 5 wt% PFA, 7.5 wt% PFA, and 10 wt% PFA coating, respectively. Among these coatings, 2.5 wt% PFA and 5 wt% PFA coatings after immersing in SBF showed good ability towards mineralization and deposition of bioactive phase components, i.e., HA and β-TCP. In contrast to other coatings prepared in this work, the presence of pore structure on the surfaces of 2.5 wt% PFA and 5 wt% PFA coatings favored the deposition of bone-like apatite. The results obtained from the cell proliferation experiment revealed that 2.5–5 wt% PFA porous coatings possessed superior cell proliferation ability when compared to the other coatings. After investigating the cell fixation morphology, the pore structures of 2.5–5 wt% PFA coatings were shown to be more beneficial for the attachment and growth of MG63 cells on the surface or within the pore structure. Furthermore, the osteoblast staining test proved an extensive wide-ranged MG63 cell growth on the surfaces of 2.5–5 wt% PFA porous coatings. The ALP activity result revealed the increase in ALP contents for 2.5–10 wt% PFA porous coatings. This was especially noticeable for 2.5 wt% PFA coating as it presented the highest ALP content after 6 days. The HYP activity result indicated a continuous HYP content increment for 0–10 wt% PFA porous coatings, with only a slight difference observed between 2 days and 6 days. Therefore, a porous gradient coating with a certain pore structure, i.e., large pore size, even pore distribution, and high pore number, could significantly influence its bioactivity and biocompatibility. Based on the collective results, 2.5 wt% PFA coating with a uniform pore distribution and numerous large-sized pores exhibited the best comprehensive bioactivity and biocompatibility.

Fabrication of Borate-Based Porous Polymer Electrolytes Containing Cyclic Carbonate for High-Performance Lithium Metal Batteries

A series of borate-based porous polymer electrolytes (B-PPEs) is prepared by incorporating the copolymers containing cyclic boroxine and cyclic carbonate groups into poly(vinylidene fluoride) (PVDF) through the phase inversion method. The dense and well-interconnected pores are obtained in the polymer matrix when the content of the copolymer reached 40 wt %. The ethylene–oxygen chain segments in the copolymer can facilitate the mobility of polymer chains and form the uniform distribution of pores in the B-PPEs. The B-PPEs show an enhanced ionic conductivity of 1.32 × 10–3 S cm–1 at 30 °C, which is due to the uniform well-interconnected pores in the polymer host. The cyclic carbonate units interact with the liquid electrolyte, which could improve the electrolyte uptake capacity of the polymer matrix. Benefited from the Lewis acid–base interactions between boron moieties and the anions of the lithium salt, the lithium-ion transference number of B-PPEs is also significantly improved. Compared to the pure PVDF-based electrolyte, the Li/B-PPEs/Li cell displays a very stable polarization voltage and the long-time cycling for 1000 h at a current density of 0.2 mA cm–2. Moreover, the Li/B-PPEs/LiFePO4 cells deliver a higher capacity of 143.0 mAh g–1 at 0.2 C and 86% capacity retention after 150 cycles. The B-PPEs could be a promising candidate for enhancing the safety and electrochemical properties of lithium metal batteries.

Graphene oxide-reinforced pectin/chitosan polyelectrolyte complex scaffolds

Three-dimensional (3D) porous scaffolds based on graphene oxide (GO) incorporated pectin/chitosan polyelectrolyte complex (PCGO) were prepared by the freeze-drying technique. The chemical composition and microstructure of the prepared PCGO scaffolds were studied by FTIR and XRD analysis. The presence of GO and its uniform distribution within the polymer matrix was confirmed by Raman spectroscopy and confocal Raman mapping analysis, respectively. TGA analysis revealed that the addition of GO improves the thermal stability of the pectin/chitosan complex. SEM analysis confirmed the uniform pore distribution of PCGO scaffolds. Moreover, it showed that the pore size of the scaffolds was decreased with the increase in GO content. Among the developed PCGO scaffolds, the scaffolds with 1 wt.% of GO presented the improved hydrophilicity by exhibiting the water swelling degree of 2004%, water retention capacity of 1101% and water contact angle (WCA) of 21°. In addition, these scaffolds presented better compressive strength (∼283 kPa) and resistance towards lysozyme-mediated degradation. The PCGO scaffolds presented an acceptable level of bio-and hemocompatibility and GO concentration-dependent cell attachment ability. These results demonstrate the suitability of PCGO scaffolds for tissue engineering.

Clinical Efficacy of Polycaprolactone β-Calcium Triphosphate Composite for Osteoconduction in Rabbit Bone Defect Model.

The combination of β-tricalcium phosphate (β-TCP) with polycaprolactone (PCL) has been considered a promising strategy for designing scaffolds for bone grafting. This study incorporated PCL with commercially available β-TCP (OsteoceraTM) to fabricate an injectable bone substitute and evaluate the effect of PCL on compressive strength and setting time of the hydraulic cement. The mechanical testing was compliant with the ASTM D695 and ASTM C191-13 standards. Results showed that PCL-TCP composite presented a well-defined architecture with uniform pore distribution and a significant increase in compressive strength compared with β-TCP alone. Eighteen rabbits, each with two surgically created bone defects, were treated using the PCL-TCP composites. The composite materials were resorbed and replaced by newly formed bone tissue. Both PCL-TCP and β-TCP demonstrated equivalent clinical effects on osteoconduction property in terms of the percentage of newly formed bone area measured by histomorphometric analysis. PCL-TCP was proven to be as effective as the commercially available β-TCP scaffold (OsteoceraTM).

Electrocatalytic composite membrane with deep-permeation nano structure fabricated by flowing synthesis for enhanced catalysis

An electrocatalytic composite membrane with deep-permeation nano structure (DPNS) has been fabricated by flowing synthesis. The nano electrocatalyst MnO2 is in situ successfully assembled in membrane pores and uniformly immobilized in membrane pores along the direction of membrane thickness. The size of MnO2 nanoparticles immobilized in membrane pores is in the range of 33–35 nm, which is one-tenth of that immobilized on the membrane surface. The increased current density and the lower charge transfer resistance of the electrocatalytic composite membrane implied that a fast electron transfer can be achieved. As a concept-of-proof, the removal of phenol was applied to test the catalytic performance of the electrocatalytic composite membrane under the flow-through reaction mode, and the removal rate of phenol of being over 97% can be achieved under the condition of membrane flux of being 13.5 L m−2 h−1. The apparent reaction rate constant could be increased by 2–3 orders of magnitude, owing to the enhanced contact by uniform distribution of membrane pores, as well as the confined space effect of membrane pores and the flow-through synergism enhancing mass transfer. The species of free radical can be determined as ·OH via ESR measurements for phenol oxidation. This electrocatalytic composite membrane (ECCM) with DPNS has good reusability and can provide a promising prospect for industrial application.

Production of wheat germ oil containing multilayer hydrogel dressing

A composite wound dressing has been developed by combining different layers consisting of polymers and textiles. Wheat germ oil (WGO) loaded hydrogels have successfully formed on textile nonwovens by cross-linking sodium alginate (SA) with poly(ethylene glycol) diglycidyl ether (PEGDGE). Following freeze-drying, textile-hydrogel composites have been examined according to their physical properties, pH, fluid handling capacity, water vapour permeability, morphology, chemical structure, and cytotoxicity. Hydrogels containing WGO swelled less than pristine hydrogels. Samples with 1% WGO and no WGO showed swelling of 5.9 and 10.5 g/g after 8 h. WGO inclusion resulted in reduced, but more stable fluid handling properties, with more uniform pore distribution (100–200 μm). Moreover, the proliferation of NIH/3T3 cells significantly improved with 1% WGO contained hydrogels. Also, commercial self-adhesive dressings that secure the hydrogels to the wound area were investigated regarding transfer properties. The proposed product demonstrated 8.05 cm3/cm2/s and 541.37 g/m2/day air and water vapour permeability.

Microscopic Pore Structure and Improved Permeability Characterization of CO x Argillite Based on SEM Images

Permeability is one of the important parameters to evaluate the long-term sealing performance of Callovo-Oxfordian (COx) argillite for high-level radioactive waste repository. In this study, scanning electron microscope images were used to analyze the pore structure of COx argillite. The pore size distributions (PSD) obtained by the discrete algorithm and two continuous algorithms (Munch continuous algorithm and Song algorithm) are quite different, the range of pore size obtained by the discrete algorithm is larger than those obtained by continuous algorithms. The results of continuous algorithms are closer to that from mercury intrusion porosimetry. For the permeability prediction, the continuous methods show better results, but there is still a big gap. By further considering the contribution of pores with different sizes to permeability, the results obtained by continuous methods are very close to the measured result. The values of A2 obtained by the Munch continuous algorithm are 2.2 × 10−16, 1.8 × 10−16, and 0.94 × 10−16 m2 for magnifications ranging from 2,000 to 8,000 times; the corresponding values obtained by the Song algorithm are 2.42 × 10−16, 2.02 × 10−16, and 1.12 × 10−16 m2, respectively, while the laboratory result is 1.67 × 10−16 m2. More accurate permeability can be obtained by more representative PSD. Therefore, for soil materials with uniform pore distribution, more accurate permeability can be obtained by considering continuous algorithms and pore contribution rate.