Porosity Structure Research Articles

Transparent Nanofibrous Membranes with Optimized Optical Channel Structure for Window Screens

AbstractNanofibrous membranes, characterized by their flexibility, high porosity, and tunable structure, are emerging as a promising contender for advanced transparent materials with sufficient breathability and pliability. However, the considerable surface light reflection and internal light scattering of nanofibrous membranes pose a challenging task in achieving transparency. In this study, transparent nanofibrous membranes are fabricated by constructing a topological structure with optimized optical transmission channels, which provide the minimum equivalent thickness to minimize light loss in nanofibrous membranes. The resultant fabricated membrane exhibits a high light transmittance of up to 81%, along with a sufficient porosity of 84% and flexibility. Additionally, the membrane demonstrated effective PM0.3–10 removal efficiency (>91%), low air pressure drops (<110 Pa), high air permeability (≈104 mm s−1), and good waterproof performance. Therefore, the prepared transparent nanofibrous membrane may serve as a transparent air filtration window screen to enhance indoor comfort for people.

Coupling control of organic and inorganic rock components on porosity and pore structure of lacustrine shale with medium maturity: A case study of the Qingshankou Formation in the southern Songliao Basin

Shale components affect organic–inorganic diagenesis, control the formation and evolution of pore structure, and lead to heterogeneity of shale reservoirs. Therefore, revealing the coupling control of shale components on the porosity and pore structure is crucial for selecting the dominant lithofacies. In this study, the lacustrine shale with medium maturity in the first member of the Qingshankou Formation (Qing1 Member) in the Changling Sag, southern Songliao Basin, China, was analyzed. Using pressurized sealed original shale samples and 2-D nuclear magnetic resonance (2D-NMR) analysis, the effective porosity of shale was accurately determined. The pore structure was characterized via experiments such as low-temperature nitrogen adsorption, NMR, and scanning electron microscope (SEM) analyses. In addition, the joint influences of the shale rock components, sedimentary structure, and maturity on the porosity and pore structure were investigated. Finally, the favorable reservoirs in the lacustrine shale with medium maturity and their formation conditions were identified. Studies have shown that for lacustrine shale with medium maturity: (1) a moderate total organic carbon (TOC) content (between 1% and 2.5%) is a key factor for improving the effective porosity and the proportions of mesopores (100–1000 nm) and small-pores (30–100 nm). This is related to the generation of organic acids and the cracking of organic matter into pores. An excessive TOC content can lead to increased plasticity of the rock and filling of the pores by bitumen. (2) The porosity and pore structure are controlled by the organic matter and inorganic minerals as well as sedimentary structure. Organic matter has dual impacts on the porosity improvement related to clay minerals, promotion of clay conversion and filling of clay-related pores, and the ratio of the clay content to the TOC (Vsh/TOC) can reflect the degree of influence of organic matter, the greater the Vsh/TOC ratio is, the greater the effective porosity and proportion of micropores are. (3) Organic matter and felsic minerals jointly effect the improvement of the effective porosity and larger pores (>30 nm), which is related to their good compression resistance, organic pore retention, and dissolution-enhanced porosity effect. The product of the TOC and felsic mineral content (Vsi*TOC) can reflect the degree of their coupled effect. For moderate TOC contents, a higher felsic mineral content, and moderate shell laminae (Vca>10%) are conducive to the development of the effective porosity and larger pores. (4) The organic medium-rich argillaceous laminated felsic shale and organic-medium argillaceous laminated clayey shale have a higher effective porosity and higher proportion of larger pores, making them the dominant lithofacies for shale oil sweet spots.

Pressure drop and heat transfer properties for normal weight and lightweight pervious concrete

This study examines the performance of pervious concrete when used for heating and cooling through forced air conditions. The influence of aggregate type, water-cement ratio, and paste volume on the air flow characteristics were examined through experimental evaluation of 10 mixes. The thermal properties and sensible heat energy stored in the pervious concrete were evaluated by measuring temperature changes with hot air flow. The results show that at a velocity of 0.35 m/s, the pressure drop falls within the range of 500 Pa/m to 8000 Pa/m. The pressure drop increases with an increase in the volume of paste to volume of aggregate ratio and decreases in water/cement ratio due to changes in the porosity and interconnected void structure of the pervious concrete. A modified pressure drop formulation based on the porosity, volume of paste to aggregate, and water/cement ratio is developed which provides a reasonable prediction for pervious concrete. The energy stored in the concrete can be accurately estimated based on the measured specific heat of the pervious concrete.

Porous Nano-Fiber Structure of Modified Electrospun Chitosan GBR Membranes Improve Osteoblast Calcium Phosphate Deposition in Osteoblast-Fibroblast Co-Cultures.

Desirable characteristics of electrospun chitosan membranes (ESCM) for guided bone regeneration are their nanofiber structure that mimics the extracellular fiber matrix and porosity for the exchange of signals between bone and soft tissue compartments. However, ESCM are susceptible to swelling and loss of nanofiber and porous structure in physiological environments. A novel post-electrospinning method using di-tert-butyl dicarbonate (tBOC) prevents swelling and loss of nanofibrous structure better than sodium carbonate treatments. This study aimed to evaluate the hypothesis that retention of nanofiber morphology and high porosity of tBOC-modified ESCM (tBOC-ESCM) would support more bone mineralization in osteoblast-fibroblast co-cultures compared to Na2CO3 treated membranes (Na2CO3-ESCM) and solution-cast chitosan solid films (CM-film). The results showed that only the tBOC-ESCM retained the nanofibrous structure and had approximately 14 times more pore volume than Na2CO3-ESCM and thousands of times more pore volume than CM-films, respectively. In co-cultures, the tBOC-ESCM resulted in a significantly greater calcium-phosphate deposition by osteoblasts than either the Na2CO3-ESCM or CM-film (p < 0.05). This work supports the study hypothesis that tBOC-ESCM with nanofiber structure and high porosity promotes the exchange of signals between osteoblasts and fibroblasts, leading to improved mineralization in vitro and thus potentially improved bone healing and regeneration in guided bone regeneration applications.

Structure and mechanical properties of PR-03N18K9M5TYu steel grade fabricated by selective laser melting and post-processing

We fabricate samples of PR-03N18K9M5TYu steel (equivalent to ChS4) using selective laser melting (SLM) in a nitrogen atmosphere. Our research focused on the influence of hot isostatic pressing (HIP) combined with heat treatment (HT), specifically hardening and aging, on the steel's structure and its physical and mechanical properties (σucs, σys, δ, ψ). Through tensile testing, we evaluated the impact of post-processing treatments (HIP followed by HT) on the material's strength. We also assessed how different post-processing protocols affected residual porosity. Our findings indicate that samples exhibiting the highest strength and plastic properties correspond to those with the least structural defects and minimal residual porosity. In-depth microstructural analysis revealed that the optimal structure–a fine-grained, homogeneous configuration–is achieved via the combined application of SLM, HIP, and subsequent HT. The improvement in mechanical properties can be primarily attributed to the dispersed hardening effect, which is a consequence of the precipitation of the superfluous Ni3Ti phase. Fractographic examination revealed that the post-processing leads to a ductile and dimple fracture, occurring through mechanisms of shearing and detachment, giving rise to mixed-type fractures. The samples that displayed superior mechanical properties were characterized by a homogenous ductile intergranular fracture surface with clear evidence of plastic deformation. We measured the hardness (Н), modulus of elasticity (Е), and elastic recovery via indentation methods. The post-processing treatments notably enhanced material hardness and elastic modulus, with an increase from H = 4.6 GPa and E = 194 GPa in the sample post-HIP to H = 8.5 GPa and E = 256 GPa following HIP coupled with hardening and aging.

Short beam shear performance of spread‐tow woven stitched composite with anti‐sandwich structure

AbstractSpread‐tow woven fabrics (STW) have attracted considerable attention because of their ultrathin structure and low porosity, which benefit the design and application of STW composites. Little is known about how the thickness relationship between the middle and surface layers affect the mechanical properties of sandwich structures. Therefore, this study developed an anti‐sandwich stitched composite with STW in the center and a nonwoven felt/STW hybrid on both sides. The interlayer shear behavior and damage mode transformation of STW composites with different middle‐layer thicknesses were studied using short‐beam shear tests, digital image correlation (DIC) full‐field strain nephograms and micro‐computed tomography (micro‐CT). The results showed that the anti‐sandwich structure improved the shear strength, particularly when the middle layer thickness was four times that of the surface layer. As the middle layer thickness ratio decreased, the synergistic effect of the anti‐sandwich structure was weakened, and the damage mode changed from ductile to brittle. Furthermore, the hybrid ratio of the STW/nonwoven fabric in the surface layer had little effect on the performance because of the good interfacial adhesion between the STW and nonwoven fabric. The anti‐sandwich structure that can improve the properties and stability of STW composites provides a reference for the structural design of STW composites in engineering applications.Highlights An anti‐sandwich composite was developed by spread tow woven fabrics. Nine types of anti‐sandwich composite were designed and fabricated. The thickness of the middle layer affected the synergistic mechanisms. The optimal anti‐sandwich structure has a 4.59% increase in shear strength. The specific shear strength is 14.86% higher over pure spread tow laminates.

Mapping of Groundwater Potential Zones in the Kuzhithuraiyar Sub Basin of Kodayar River, Kanniyakumari District, Tamilnadu: Using Analytic Hierarchy Process (AHP) and GIS

&#x0D; &#x0D; &#x0D; Groundwater plays a very important role for all living beings. It is decisive to have a scientific understanding of groundwater management since, with careful use and replenishment, groundwater may help solve issues. The distribution of groundwater tables, slope, land-form, drainage pattern, lithology, topography, geological structure, fracturing density, opening and connectivity of fractures, secondary porosity, and landuse landcover all affect the occurrence and efficiency of groundwater in an aquifer system. An essential tool for assessing, tracking and protecting groundwater resources is the integration of geospatial techniques such as Remote Sensing and Geographic Information System for the identification of groundwater potential zones. This study aims to find the groundwater potential zones using Analytical Hierarchy Process (AHP) and managing the resources by creating different thematic layers such as rainfall, geology, geomorphology, drainage density, soil, slope, lineament and landuse landcover (LULC) of the Kuzhithuraiyar sub basin of the Kodayar river in Tamilnadu using the application of geospatial technologies. The thematic maps for all the thematic layers have been prepared using tools such as Interpolation, contour lines, Classification in ArcGIS 10.8. Theme weight and class rank were assigned to different thematic layers in weighed overlay analysis. The results were validated through field work and groundwater potential map was created. The groundwater potential zonation mapping was done by the overlay analysis in ArcGIS 10.8 software. The obtained map was classified into four categories namely very high groundwater potential zone, high groundwater potential zone, medium groundwater potential zone and low groundwater potential zone. The North Eastern part of the basin is considered as low groundwater potential zone while the Southern portion has high groundwater potentiality. The low groundwater potential zone covers an area of 10.58 sq.km and high groundwater potential zone covers an area of about 388.37sq.km.This study will be helpful for useful groundwater management for different tenacities.&#x0D; &#x0D; &#x0D;

Revealing the Charge Storage Mechanism in Porous Carbon to Achieve Efficient K Ion Storage.

Constructing a porous structure is considered an appealing strategy to improve the electrochemical properties of carbon anodes for potassium-ion batteries (PIBs). Nevertheless, the correlation between electrochemical K-storage performance and pore structure has not been well elucidated, which hinders the development of high-performance carbon anodes. Herein, various porous carbons are synthesized with porosity structures ranging from micropores to micro/mesopores and mesopores, and systematic investigations are conducted to establish a relationship between pore characteristics and K-storage performance. It is found that micropores fail to afford accessible active sites for K ion storage, whereas mesopores can provide abundant surface adsorption sites, and the enlarged interlayer spacing facilitates the intercalation process, thus resulting in significantly improved K-storage performances. Consequently, PCa electrode with a prominent mesoporous structure achieves the highest reversible capacity of 421.7 mAh g-1 and an excellent rate capability of 191.8 mAh g-1 at 5C. Furthermore, the assembled potassium-ion hybrid capacitor realizes an impressive energy density of 151.7Wh kg-1 at a power density of 398W kg-1. The proposed work not only deepens the understanding of potassium storage in carbon materials with distinctive porosities but also paves a path toward developing high-performance anodes for PIBs with customized energy storage capabilities.

Facile synthesis of N-doped biomass derived porous carbon from Opuntia humifusa using simple solid state activation method for reversible capture of volatile iodine

The search for adsorbent materials capable of extracting and storing radioactive iodine derived from nuclear power plants has intensified owing to the growing nuclear waste concerns. Herein, we report a novel method, which is simple and effective, to synthesize biomass-derived porous carbon from an easily available biomass, Opuntia humifusa, via simple solid-state activation with zinc chloride. The resulting porous carbon exhibits a large specific surface area, with up to 1869 m2/g of micropores. The textural properties of activated carbons can be easily modified by adjusting the amount of zinc chloride and activation temperature. The optimal conditions were found to be a ZnCl2 to biomass ratio of 5 and a carbonization temperature of 500 °C. The obtained porous carbons can function as multifunctional solid sorbents for radioactive iodine because of their high porosity and advantageous hierarchical porous structure. Specifically, the obtained activated carbon exhibited high iodine affinity with an absorption of 408 wt%. Considering its global abundance and recyclability, Opuntia humifusa can be used as a new biomass source for the efficient production of highly effective porous carbon materials with potential applications in environmental restoration. Furthermore, the straightforward single-step synthesis method described in this study offers a technique for producing several unique activated mesoporous carbons from various biomasses.

Integration of space-holder technique and spark plasma sintering: An innovative approach for crafting radially graded porosity implants

Bone resorption and possible fracture of host tissue are some consequences resulting from the mismatch between the Young's Modulus of the constituent materials of implants and bone that compromises the reliability of implants for replacing damaged bone tissue. The use of functional graded porous materials presents an interesting approach that could help decrease the Young's modulus while simultaneously mimicking highly hierarchical porosity of the bone structure. However, these structures are more difficult to fabricate than those with homogenous porosity. The design and distribution of this porosity in the implant must ensure the biomechanical and biofunctional balance of the bone tissue it is intended to replace. In this study, Ti radially graded structures were successfully fabricated using Spark Plasma Sintering combined with Space Holder Technique. The effects of temperature on porosity and mechanical properties were thoroughly examined. The results indicated that this processing route allows to achieve good control of porosity, close to the amount of added spacer. Yield stress of 181 MPa and an elastic modulus of 56 GPa were obtained for samples sintered at 800 °C for 5 min under a pressure of 6.3 MPa. These mechanical properties make the structure a viable candidate for replacing human long bones.

Mechanically Enhanced Detoxification of Chemical Warfare Agent Simulants by a Two-Dimensional Piezoresponsive Metal-Organic Framework.

Chemical warfare agents (CWAs) refer to toxic chemical substances used in warfare. Recently, CWAs have been a critical threat for public safety due to their high toxicity. Metal-organic frameworks have exhibited great potential in protecting against CWAs due to their high crystallinity, stable structure, large specific surface area, high porosity, and adjustable structure. However, the metal clusters of most reported MOFs might be highly consumed when applied in CWA hydrolysis. Herein, we fabricated a two-dimensional piezoresponsive UiO-66-F4 and subjected it to CWA simulant dimethyl-4-nitrophenyl phosphate (DMNP) detoxification under sonic conditions. The results show that sonication can effectively enhance the removal performance under optimal conditions; the reaction rate constant k was upgraded 45% by sonication. Moreover, the first-principle calculation revealed that the band gap could be further widened with the application of mechanical stress, which was beneficial for the generation of 1O2, thus further upgrading the detoxification performance toward DMNP. This work demonstrated that mechanical vibration could be introduced to CWA protection, but promising applications are rarely reported.

Fabrication of 3D porous polyurethane-graphene oxide scaffolds by a sequential two-step processing for non-load bearing bone defects

Bone defects as a common orthopedic disease lead to severe pains over a long period. Scaffolds are novel approaches in tissue engineering to treat bone problems and deal with their challenges. Here, 3D porous polyurethane (PU) scaffolds containing graphene oxide (GO) with different percentages (0, 0.1, 0.3, and 0.5 wt%) were developed through a combination of freeze-drying and salt etching techniques for bone tissue engineering applications. The morphologies of scaffolds, physicochemical properties, the degree of crystallinity, and hydrophilicity were evaluated by SEM, FTIR, XRD, and water contact angle assay, respectively. The porosity, degradation behavior, compressive strength, and elastic modulus of 3D porous scaffolds were also determined. To assess the scaffold bioactivity, the morphology of the deposited calcium phosphate layer on the scaffold with macro-structure was evaluated by SEM images. The viability and adhesion of MG63 osteoblast-like cells cultured on the fabricated scaffolds were examined by MTT assay and SEM images, respectively. The results show that adding GO particles not only had no effect on the interconnectivity and porosity of 3D porous macroscopic structures of neat PU but also smaller and more uniformed microscopically pores were obtained. The crystallinity, water contact angle, and weight loss of scaffolds increased as the higher GO concentrations were employed. Followed by increasing GO contents from 0 to 0.5 wt%, the compressive strength and Young’s modulus were increased by 232% and 245%, respectively. The bioactivity of scaffolds was fostered as GO concentration increased. Although, the MTT assay proved the biocompatibility of PU scaffolds containing 0.1 and 0.3 wt% GO, the samples loaded with 0.5 GO had a negative impact on the viability of MG63 cell lines. In conclusion, the present study demonstrates a high potential of PU scaffolds loaded with 0.1 and 0.3 wt% GO particles in bone tissue engineering applications.

The Overlooked Potential of Sulfated Zirconia: Reexamining Solid Superacidity Toward the Controlled Depolymerization of Polyolefins.

Closed-loop recycling via an efficient chemical process can help alleviate the global plastic waste crisis. However, conventional depolymerization methods for polyolefins, which compose more than 50% of plastics, demand high temperatures and pressures, employ precious noble metals, and/or yield complex mixtures of products limited to single-use fuels or oils. Superacidic forms of sulfated zirconia (SZrO) with Hammet Acidity Functions (H0) ≤ - 12 (i.e., stronger than 100% H2SO4) are industrially deployed heterogeneous catalysts capable of activating hydrocarbons under mild conditions and are shown to decompose polyolefins at temperatures near 200 °C and ambient pressure. Additionally, confinement of active sites in porous supports is known to radically increase selectivity, coking and sintering resistance, and acid site activity, presenting a possible approach to low-energy polyolefin depolymerization. However, a critical examination of the literature on SZrO led us to a surprising conclusion: despite 40 years of catalytic study, engineering, and industrial use, the surface chemistry of SZrO is poorly understood. Ostensibly spurred by SZrO's impressive catalytic activity, the application-driven study of SZrO has resulted in deleterious ambiguity in requisite synthetic conditions for superacidity and insufficient characterization of acidity, porosity, and active site structure. This ambiguity has produced significant knowledge gaps surrounding the synthesis, structure, and mechanisms of hydrocarbon activation for optimized SZrO, stunting the potential of this catalyst in olefin cracking and other industrially relevant reactions, such as isomerization, esterification, and alkylation. Toward mitigating these long extant issues, we herein identify and highlight these current shortcomings and knowledge gaps, propose explicit guidelines for characterization of and reporting on characterization of solid acidity, and discuss the potential of pore-confined superacids in the efficient and selective depolymerization of polyolefins.

High thermal conductivity and high energy density compatible latent heat thermal energy storage enabled by porous Al2O3@Graphite ceramics composites

Phase change material (PCM) is an ideal heat storage material with huge latent heat and nearly constant phase change temperature, but there are serious problems in application such as leakage and low thermal conductivity. Porous ceramic is widely used in PCM packaging because of its advantages of controllable porosity and high thermal conductivity. Porous Al2O3 ceramics were prepared by foaming injection coagulation method. In order to improve the thermal conductivity of porous ceramic matrix, Porous Al2O3@Graphite Ceramics (PAGC) were prepared by sucrose decomposition. Form-Stable Phase Change Materials (FSPCMs) were prepared by adsorption of Lauric Acid/Myristic Acid (LA/MA) in PAGC by vacuum impregnation method. SEM showed that the prepared PAGC had a three-dimensional interpenetrating structure and high porosity. TEM and XPS showed that alumina skeleton were uniformly coated with graphite. After PAGC impregnated by LA/MA, the maximum PCM storage reached 62.11 wt %. The maximum latent heat of FSPCMs reaches 83.33 J/g. Thermogravimetric analysis, thermal cycling test and Fourier transform infrared spectroscopy show that the prepared FSPCMs has good thermal stability, thermal reliability, chemical stability and compressive strength. More importantly, the thermal conductivity of the prepared FSPCMs is greatly improved, reaching up to 3.73 W/mK. It is 20.72 times the original PCM, mainly due to the synergistic effect of the Al2O3 skeleton and the graphite coating to build a continuous highway for heat transfer. This study provides a practical means to greatly improve the thermal conductivity of FSPCMs, which will promote the practical application of FSPCMs.

3D printed multifunctional hierarchical structured cellular silicones with ultraelasticity, extreme load-bearing capacity, shape morphing and sensing properties

Multifunctional lightweight cellular silicone with adjustable properties has aroused great interests in many fields. However, it remains a challenge to facilely prepare multifunctional lightweight porous silicones with high load-bearing capacity. Herein, this work developed a 3D printing technique to prepare lightweight hierarchical structured cellular silicones with macroscale lattice structure and microscale intra-strand close-cell porosities, which was achieved by the expansion of thermally expandable microspheres (TEM) with plastic shells dispersed in formulated silicones. The obtained silicone foam with hierarchical porosity distributions shows excellent mechanical properties, including extreme load-bearing capacity (load is more than 165000 times its weight), high elasticity (negligible stress and strain loss under 80% compression), and high cycle durability (less than 4% strain loss under 1000 compression cycles). Besides, the incorporation of conductive fillers of MWCNTs endowed the foam with multifunctional piezoresistive and temperature-sensing properties. Furthermore, by printing multiple mixture inks of varying expansion ratios, shape morphing ability was endowed to the printed foam, to achieve complex curvature geometry facilely, demonstrating excellent versatility and potential applications in manufacturing flexible and conformal electronics of this method.

Fabrication of biomimetic scaffold through hybrid forming technique

AbstractBone tissue engineering procedures require the use of a scaffold with a sufficiently porous structure, which serves as a three‐dimensional template for cell attachment, followed by tissue regeneration and vascularization both in vitro and in vivo. This study aimed to create scaffold material with a unique hybrid forming that met these parameters. Slip casting and freeze‐drying processes were used with a hybrid forming approach to create a bone scaffold based on hydroxyapatite (HA) mimicking the structure of cortical and cancellous bones, respectively. HA was synthesized by the wet chemical precipitation method. Fourier‐transform infrared spectroscopy, dynamic light scattering, X‐ray diffraction, thermogravimetric analysis‐differential thermal analysis, Brunauer‐Emmett‐Teller, He Pycnometer, and scanning electron microscope analyses were performed to characterize the scaffold. According to analysis results, HA particle size was found at 137.8 nm. The optimum sintering temperature was determined to be 1300°C. The specific surface area of the HA powder was measured as 55.11 m2/g. The total open porosity of the hybrid scaffold was calculated as 70%. Scaffold successfully substituted both cancellous and cortical layers of bone regarding structural characteristics, porosity, and mechanical strength. Considering morphological characteristics, a hybrid scaffold might facilitate vascularization, osteoinduction, and osteoconduction. Research findings suggest that the hybrid design strongly resembled natural bone and is suitable for both load‐bearing and non‐bearing bones.

Structural/surficial dual regulated granular H2TiO3 lithium-ion sieves for lithium extraction from salt lake brine

H2TiO3 (HTO) is recognized as a highly promising lithium-ion sieve (LIS) material for lithium resources extraction from the liquid phase, attributed to its high theoretical capacity, stable structure, and excellent recyclability. However, when directly employed in continuous flow systems, the powder HTO-LIS encounters significant challenges, including elevated energy consumption and persistent material loss, impeding its practical application. Therefore, it is necessary to granulate the powder LIS material, which nevertheless results in the reduction of the specific capacity and Li extraction rate. Herein, a hybrid binder (cellulose acetate/sulfonated poly(ether ketone)/poly(vinyl chloride)) is employed for granulation and immobilization of the powder HTO-LIS. This approach regulates the porosity structure, hydrophilicity, surface charge character, and mechanical strength of the granulated LIS, thereby synergistically enhancing Li extraction capacity (26.54 mg g−1), recovery kinetics (19.02 mg g−1 within 4 h), and dynamic cycling stability (adsorption capacity retention of 94.02% after 40 cycles). This work proposes a feasible granulation strategy, contributing to advance the industrialization of LIS materials.

Insight into the mechanisms of combining direct current magnetic field with phosphate in promoting emulsifying properties of myofibrillar protein

This study investigated the combined effects of direct-current magnetic field (DC-MF, 9.5 mT) and tetrasodium-pyrophosphate (TSPP, 1-5 g/L) on emulsified gel properties of porcine myofibrillar protein (MP). Results showed that MP at DC-MF and 3 g/L TSPP had decreased spectrum intensity of UV and fluorescence compared to that without DC-MF, owing to the changes of MP tertiary structure caused by DC-MF, especially tryptophan and tyrosine. The emulsion treated with DC-MF behaved better emulsifying activity and stability than that without DC-MF under such condition. And emulsion had lower creaming index and better storage stability. Gels prepared by this MP emulsion had low porosity and stable structure, accompanying with smaller size and more uniform distribution of oil droplets. Microstructure images showed that gels were covered with microporous structure, which was conducive to the good WHC of the emulsified gels (97.12%). These results showed the feasibility of DC-MF and TSPP in improving MP emulsion/emulsified gel.

Predicting carbonate rock dissolution using multi-scale residual neural networks with prior knowledge

The factors that affect carbonate dissolution are complex, and it is crucial to acquire efficient and accurate knowledge of carbonate dissolution characteristics for CO2 capture and storage (CCS) projects. In current research, the most precise outcomes can be achieved through experimental or simulation techniques, but they are frequently computationally demanding and time-consuming. Data-driven machine learning methods can efficiently perform regression prediction tasks. In this paper, we propose a multi-scale hierarchical regression model for the dissolution problem based on residual neural networks, incorporating prior knowledge. We have developed new equations for carbonate rock dissolution and have incorporated the factors that influence this process into 3D image data by introducing Dissolution Degree (Dd) parameters. This allows the image data to include both the pore space structure and dissolution information with physical meaning. We utilize the pore phase and matrix phase grayscale thresholds (Pt, Mt) to eliminate voxel noise in the characteristic maps obtained from the model. This ensures that the predicted characteristics of carbonate rock dissolution are consistent with practical physics knowledge. We selected a total of 5 core samples to test the model. Among them, three samples are from the test set, and the additional two core samples selected have strong and weak correlations with the training set samples, respectively. The predictions were evaluated using semantic segmentation evaluation parameters, porosity, geometrical and topological structure parameters, Péclet and Damköhler numbers, porous media flow field simulations, and absolute permeability. The results of both visual comparisons and quantitative analyses demonstrated a high degree of consistency between predicted and experimental results, and the trained multi-scale hierarchical regression residual neural network with prior knowledge (MSR-Net) demonstrates good accuracy and generalization ability. The results of this study demonstrate that model based on MSR-Net can be utilized to predict the dissolution properties of the pore space in the formation where the core was extracted, along with the related formation.

Multiscale design and digital light processing preparation of high-strength SiOC ceramic metastructures for tuning microwave absorption properties

Silicon oxycarbide (SiOC) ceramics have been used to fabricate microwave-absorbing metastructures, demonstrating impressive absorption capabilities. However, SiOC ceramic metastructures with excellent performance require simple fabrication processes and appropriate mechanical and electromagnetic properties. In this study, a solvent-free photosensitive polysiloxane preceramic was developed by blending methoxy/hydroxy polysiloxanes with acrylates, with a ceramic yield of over 60% after curing using a novel two-step ultraviolet (UV)/thermal method. The composition and microstructure of SiOC ceramics can be designed by controlling the preceramic composition. Dense, crack-free gyroid-shellular shaped triple periodic minimal surface (GS-TPMS) electromagnetic metastructures were fabricated using digital light processing (DLP) 3D printing technology. By designing the porosity of the GS-TPMS structure to 51%, an effective absorption bandwidth that covers the X-band can be achieved at a thickness of 3.1 mm. The honeycomb structure, with a geometric density of 0.69 g/cm3, exhibited a high compressive strength of 107.05 MPa. This paper presents an efficient approach for the prompt and customized fabrication of lightweight ceramic metastructures with outstanding microwave absorption properties.