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In this work, the deformation behavior of porous ceramics ZrO2–5.5 wt.% Y2O3 with different morphology of the pore space under axial quasi-static compression is studied by the digital image correlation (DIC) method. Two stages of the deformation behavior of the ceramics have been identified, namely, the controlled accumulation of microcracks and the formation of block structures. It has been found that an increase in the average pore size leads to a decrease in the tensile strength, a decrease in the effective elasticity modulus, and an increase in the ultimate deformation, while the nature of the deformation macrolocalization changes from ordered to chaotic one. It is shown that the rate of accumulation of local deformations in the central part of the deformable sample with a pore size of 68 μm is several times higher than in the sample with a pore size of 29 μm. [ABSTRACT FROM AUTHOR]

Relative permeability is a key parameter for characterizing the multiphase flow dynamics in porous media at macroscopic scale while it can be significantly impacted by wettability. Recently, it has been reported in microfluidic experiments that wettability is dependent on the pore size (Van Rooijen et al., 2022). To investigate the effect of pore‐size‐dependent wettability on relative permeability, we propose a theoretical framework informed by digital core samples to quantify the deviation of relative permeability curves due to wettability change. We find that the significance of impact is highly dependent on two factors: (i) the function between contact angle and pore size (ii) overall pore size distribution. Under linear function, this impact can be significant for tight porous media with a maximum deviation of 1,000%. Plain Language Summary: Relative permeability is an important feature for multiphase flow at the reservoir scale. It can be highly dependent on wettability, which is an interfacial property at the pore scale. Recent experimental evidence suggests that wettability is dependent on the pore size, but the impact of the pore‐size‐dependent wettability on relative permeability still remains unknown. In this study, we propose a theoretical model to investigate the effect of pore‐size‐dependent wettability on relative permeability. The pore size distribution is informed by the pore images. We find that the impact can be significant for low‐permeability porous media under certain conditions. The results imply that this effect is not always neglible when modeling two‐phase flow. Key Points: A theoretical framework is proposed to quantify the impact of pore‐size dependent wettability on relative permeabilityThe maximum impact on relative permeability can be as significant as 1,000% [ABSTRACT FROM AUTHOR]

Measurements of the thermal conductivity were performed as a function of gas pressure from 10–1 hPa up to 105 hPa on several bimodal silica xerogels. The xerogels exhibit a mesopore and a macropore phase. The measurements were done using a hot-wire apparatus, which can do automated, gas pressure-dependent measurements of the thermal conductivity from 10–3 up to 105 hPa. Results were fitted with a bimodal gas pressure-dependent thermal conductivity model to gain information on the thermal conductivity of the materials, its various contributions and on structural parameters such as the two main pore sizes, the macro- and mesoporosities. The pore sizes and porosities were compared to values gained from mercury porosimetry and nitrogen adsorption measurements. The porosities from the thermal conductivity measurements are in very good agreement to the other measuring methods. The macropore sizes from the thermal conductivity measurements are mostly in agreement within the given uncertainty range and the mesopore sizes show a good estimate of the order of magnitude of the pores. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Silicon carbide (SiC) ceramic membranes are highly sought-after for their exceptional properties including high temperature resistance, corrosion resistance, good hydrophilicity, high flux, and high mechanical strength. However, achieving stable regulation of high solid content SiC slurries for membrane preparation remains a significant challenge. This study presents a novel approach to stabilize the dispersion of high solid content SiC slurries by controlling parameters such as solid content, pH, ball milling time and spray coating parameters. Furthermore, the impact of different milling durations on SiC particle size and membrane performance is systematically investigated, establishing, for the first time, a direct correlation between milling time and particle size. The investigations reveal that prolonged ball milling, specifically 18 h, results in a notable reduction in membrane pore size by approximately 40 %, accompanied by a remarkable enhancement in retention performance, as evidenced by a substantial increase in the average retention rate for 500 nm fluorescent microspheres from 54.61 % to 98.89 %. This study not only offers a practical method for the stable preparation of ceramic slurries, but also provide important reference for membrane morphology control and pore size regulation. These insights hold significant promise for advancing SiC membrane technology in applications such as wastewater treatment and resource recovery. [ABSTRACT FROM AUTHOR]

Abstract The volume-sensitive outwardly rectifying or volume-regulated anion channel, VSOR/VRAC, which was discovered in 1988, is expressed in most vertebrate cell types, and is essentially involved in cell volume regulation after swelling and in the induction of cell death. This series of review articles describes what is already known and what remains to be uncovered about the functional and molecular properties as well as the physiological and pathophysiological roles of VSOR/VRAC. This Part 2 review article describes, from the physiological and pathophysiological standpoints, first the pivotal roles of VSOR/VRAC in the release of autocrine/paracrine organic signal molecules, such as glutamate, ATP, glutathione, cGAMP, and itaconate, as well as second the swelling-independent and -dependent activation mechanisms of VSOR/VRAC. Since the pore size of VSOR/VRAC has now well been evaluated by electrophysiological and 3D-structural methods, the signal-releasing activity of VSOR/VRAC is here discussed by comparing the molecular sizes of these organic signals to the channel pore size. Swelling-independent activation mechanisms include a physicochemical one caused by the reduction of intracellular ionic strength and a biochemical one caused by oxidation due to stimulation by receptor agonists or apoptosis inducers. Because some organic substances released via VSOR/VRAC upon cell swelling can trigger or augment VSOR/VRAC activation in an autocrine fashion, swelling-dependent activation mechanisms are to be divided into two phases: the first phase induced by cell swelling per se and the second phase caused by receptor stimulation by released organic signals.

Abstract This research delved into the influence of mesoporous silica’s surface charge density on the adsorption of Cu2+. The synthesis of mesoporous silica employed the hydrothermal method, with pore size controlled by varying the length of trimethylammonium bromide (CnTAB, n = 12, 14, 16) chains. Gas adsorption techniques and transmission electron microscopy characterized the mesoporous silica structure. Surface charge densities of the mesoporous silica were determined through potentiometric titration, while surface hydroxyl densities were assessed using the thermogravimetric method. Subsequently, batch adsorption experiments were conducted to study the adsorption of Cu2+ in mesoporous silica, and the process was comprehensively analyzed using Atomic absorption spectrometry (AAS), Fourier transform infrared (FTIR), and L3 edge X-ray absorption near edge structure (XANES). The research findings suggest a positive correlation between the pore size of mesoporous silica, its surface charge density, and the adsorption capacity for Cu2+. More specifically, as the pore size increases within the 3–4.1 nm range, the surface charge density and the adsorption capacity for Cu2+ also increase. Our findings provide valuable insights into the relationship between the physicochemical properties of mesoporous silica and the adsorption behavior of Cu2+, offering potential applications in areas such as environmental remediation and catalysis.

Abstract The compressive strength is very important for petroleum and other engineering studies. However, the effect of pore size and fluid distribution on the rock’s strength is not fully understood. We developed comprehensive research to study the controlling factors of the compressive strength based on low field nuclear magnetic resonance (NMR) measurements and pseudo-triaxial compression test for tight sandstones. The relationship between the compressive strength and the NMR obtained parameters are investigated completely, aiming for a better estimation of the compressive strength using the NMR data. The result shows that the rock’s strength is strongly controlled by the pore size distribution and the fluid existing state. Generally, the compressive strength is negatively correlated with the average transversal relaxation time, the movable water saturation, and the porosity, but positively correlated with the irreducible water saturation. The result reveals that the rock with larger pore radius and higher percentage of movable fluid is easier to reach the failure state. Further, the precision of the empirical model by multiple regression of the geometric mean of the relaxation time and the porosity is greatly improved compared with the model established by the brittle minerals, which is potentially to be use for geophysical prospecting when the NMR logging data is available.

Objective： To improve the adsorption of genistein by zirconium-based metal-organic frameworks （MOFs） with triangle aromatic ligands. Methods： Two MOFs （MOF-808 and PCN-777） containing different sizes of triangle aromatic ligands were synthesized by hydrothermal method for adsorption of genistein. The synthesis of MOFs was determined by a series of characterization methods, and the adsorption performance was compared with that of a linear binary carboxylic acid ligand-constructed MOF （UiO-66）, to evaluate the effects of pore characteristics, hydrophobicity changes, and other factors on the adsorption performance, and to explore the adsorption mechanism by XPS analysis. Results： Compared with linear ligand-constructed UiO-66, the pore sizes of triangular aromatic ligand-constructed MOFs （MOF-808, and PCN-777） increased from 0.65 nm to 1.81 nm and 3.55 nm, respectively, and the water contact angles increased from 47.91° to 110.68° and 128.23°, respectively. The adsorption capacity and adsorption efficiency of genistein in linear ligand-constructed UiO-66 was 40.08 mg/g and 39.98%, respectively, while the adsorption capacity and adsorption efficiency of genistein in MOFs constructed by triangular aromatic ligand （MOF-808, PCN-777） was increased to 61.80 mg/g, 81.75 mg/g and 61.63%, 81.52% respectively. Conclusion： Metal-organic frameworks （MOFs） can be used for the adsorption and enrichment of genistein. Compared with linear ligands, the introduction of triangular aromatic ligands with different sizes changes the pore size and hydrophobicity of MOFs, enhances the internal accessibility of MOFs, and provides more adsorption sites, which improves the adsorption effect of genistein. The adsorption mechanism of genistein in PCN-777 is based on the synergistic combination of metal-chelating interactions, π-π interactions, and hydrophobic interactions.

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, we aimed to develop a model for computing direct contact membrane distillation (DCMD) performance, taking into account capillary pressure effects at the liquid--gas interface within membrane pores. We developed a simulation model to investigate how factors such as pore radius, feed/permeate temperature, pressure, and contact angle influenced the distance of liquid intrusion into the pore, the weight flow rate in a single pore, and the temperature at the liquid--gas interface. The model predicted that the permeation rate would decrease with an increase in the feed pressurewhen the permeate pressure was kept constant and also when the pressure difference between the feed and permeate was kept constant. It also predicted that the permeation rate would increase with an increase in the permeate pressure when the feed pressure was kept constant. The model also indicated that partial pore wetting would be enhanced with an increase in feed pressure when the pore size was as large as 1 μm but would diminish when the pore size was as small as 0.1 μm. According to the model, partial pore wetting diminished with a decrease in the permeate pressure. The model's predictions were in line with the trends observed in the experimental DCMD flux data by many authors, particularly those regarding the effects of feed and permeate temperature and the effect of contact angle. The model's predictions were compared with the experimental data recorded in the literature, validating the model's accuracy. [ABSTRACT FROM AUTHOR]

In this work, we have designed unique poly(lactic acid- co -glycolic acid)- b -poly(ethylene oxide)- b -poly(propylene oxide)- b -poly(ethylene oxide)- b -poly(lactic acid- co -glycolic acid) pentablock copolymers using Pluronic F68 and F108 triblock copolymers as macroinitiators. The poly(lactic acid- co -glycolic acid) (PLGA) blocks were attached as glycolide and lactide monomers at the both ends of each F68 and F108 triblock copolymer. The molecular weights and the block fractions were confirmed by gel permeation chromatography (GPC) and proton nuclear magnetic resonance (1H NMR) for the four kinds of pentablock copolymers. Using these pentablock copolymers as templates, we synthesized mesoporous ethane-silicas as well as silicas by the evaporation-induced self-assembly (EISA) method. 1,2-bis(triethoxysily)ethane (BTEE) were used as an organosilica precursor. The mesoporous ethane-silica samples were characterized using synchrotron small angle X-ray scattering (SAXS), nitrogen sorption experiments, transmission electron microscopy (TEM), and solid-state 29Si CP-MAS NMR. Based on the experimental results, it was confirmed that the porosity and pore diameter can be varied with the PLGA weight fraction of the pentablock copolymer. It is due to the PLGA block in polymer forming the hydrophobic domain in micelles, which leads to the formation of increased pore size over 20 nm without any additive pore expander. In addition, it seems that as the organosilica precursor increases, the association number of block copolymers forming one micelle decreases, resulting in a decrease in pore size. In summary, the polymer template plays a vital part in tuning the structure of the mesoporous ethane-silica samples. Thus, the development of synthetic method of mesoporous organosilica materials using polymer templates with different topology is still challenging and can endow the unique structure and property for mesoporous organosilica for future applications. [ABSTRACT FROM AUTHOR]

Solar desalination, harvesting solar energy to purify seawater, has received considerable attention due to water scarcity problems caused by climate change and human activity. In this study, we investigated a membrane desalination method that collects vaporized water from the surface of a sun-lit porous medium floating on salt water. To maximize the water evaporation rate at the membrane surface, several effective photothermal converting materials were coated on the membrane. In addition, to amplify the water transport to the sun-lit surface, the pore size of the porous medium also was controlled by filtering sugar particles by size. We found that the evaporation rate increased as the reflectivity of the coating materials decreased, and demonstrate the optimized pore size, leading to improved evaporation at the three-phase interface by controlling the size of the pores. The water transport is caused by the porous medium resulted from competition between capillary and viscous forces; thus, the optimal pore size for maximum water transport and evaporation rate is discussed. The finding of this study provide insight into optimizing the design of the membrane's structure and coating materials to maximize the evaporation rate in solar desalination. [ABSTRACT FROM AUTHOR]

Propylene (C3H6) is a crucial olefin raw material used in the production of polypropylene, which is the world's second-most produced synthetic plastic. Separating propylene from propane (C3H8) is an important and significant challenge for industry due to the similar molecular sizes and physical properties of these gases. At present, the usual method for this separation is energy-intensive cryogenic distillation, which has low efficiency and high energy consumption. Therefore, an energy-efficient alternative way is in an urgent demand. Metal-organic frameworks (MOFs) are promising candidates for propylene/propane separation, thanks to the well-defined, designable, modifiable, and flexible structures. This review provides a summary of a recent development of MOFs that are able to discriminate between propylene and propane. The key factors that determine the separation performance of MOFs, primarily from the perspectives of pore size, presence of open metal sites (OMS) and MOFs membranes are summarized. Besides, the challenges that must be addressed for the further development of separations utilizing MOFs are also discussed. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) foams are created via the chemical reactions arising after the blending of two initially liquid components (polyols and isocyanates). They are widely used for thermal insulation, for which a small pore size is required. Some of the most efficient pore size–reducing agents have proven to be per- and polyfluorinated carbons (FCs) which are simply added in small quantities to the initially liquid mixture. However, despite their long-standing use, their modes of action have only recently begun to be studied in detail. One widely accepted explanation of their action is that they supposedly suppress diffusional gas exchange between bubbles in the liquid-foam state of the nascent PU foam (foam coarsening). However, using a new double-syringe mixing technique, we show that FCs actually act at a much earlier state of the process: they facilitate the entrainment of tiny air bubbles into PU foam systems during the initial blending process. These bubbles serve as sites for heterogeneous nucleation during the foaming process, and their large number leads to a significant reduction of the characteristic pore size. More importantly, we also demonstrate that the same overall relation is found between the air bubble density and the final pore size for systems with and without FC. Combined with a detailed analysis of the pore size distribution, we argue that the main pore size–reducing effect of FCs is to facilitate air entrainment and that foam aging–related effects only play a minor role. [ABSTRACT FROM AUTHOR]

Aluminium metal foams offer low density (∼10–15% of bulk material) possessing cellular structure that ensures unique features with high stiffens, better energy absorption, thermal and acoustic properties. Selection of different foaming agents for preparing AA6061 foam samples are indeed an industrial relevance for better control over porosity and its dimensions, strengths (tensile, flexural and compression) useful for distinguished applications. Three foaming agents such as wax powder, magnesium hydroxide, and titanium hydride are selected with varying 3–9 weight percentage to prepare metal foams viz. powder metallurgy technique. For the prepared foam samples the percentage porosity, pore dimensions (maximum pore size, and equivalent diameter) and strengths were examined. Wax powder foaming agent resulted with a maximum strength in foam samples compared to magnesium hydroxide and titanium hydride. Scanning electron microscope with energy dispersive spectroscopy analysis revealed that there is no evidence of foreign elements and confirm uniform distribution of porosity in the foam samples. [ABSTRACT FROM AUTHOR]

BACKGROUND: The present study investigates the in situ electrogeneration of H2O2 by the 2e− oxygen reduction reaction in an electrochemical flow cell using three commercially available cathodic electrode materials with different interfacial properties; that is, activated carbon felt (ACF), non‐activated carbon felt (NACF) and gas diffusion electrode (GDE). RESULTS: Experiments were first performed to optimize the operating parameters and to determine the yield of H2O2 electrosynthesis. The estimated maximum yield of ~40% was achieved with the NACF electrode after 30 min of operation. Furthermore, the performance of the electrodes was investigated in two scenarios, namely (i) under conditions with O2‐saturated electrolyte and (ii) under continuous air supply, to study the differences in O2 distribution within the electrode material as a function of its interfacial properties. The maximum H2O2 concentration for the first scenario was 3.86 mg L−1 after 60 min of operation, which was obtained with the NACF electrode. In contrast, in the second scenario, H2O2 electrogeneration was significantly increased for all three electrodes, with the GDE exhibiting the best performance, at 43.3 mg L−1 after 60 min of operation. CONCLUSIONS: The properties of the electrode material play a decisive role in H2O2 electrogeneration. The hydrophilicity of the electrode is very important when O2 is dissolved in the electrolyte. Hydrophobicity is preferable when gaseous O2 is applied to the electrode as a three‐phase interface is formed, which favors the transfer/penetration of O2. The pore size of the electrode is of crucial importance, as mesoporous materials facilitate the distribution of gaseous O2 in the electrode body. © 2024 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Conventional synthetic vascular grafts are associated with significant failure rates due to their mismatched mechanical properties with the native vessel and poor regenerative potential. Though different tissue engineering approaches have been used to improve the biocompatibility of synthetic vascular grafts, it is still crucial to develop a new generation of synthetic grafts that can match the dynamics of native vessel and direct the host response to achieve robust vascular regeneration. The size of pores within implanted biomaterials has shown significant effects on macrophage polarization, which has been further confirmed as necessary for efficient vascular formation and remodeling. Here, we developed biodegradable, autoclavable synthetic vascular grafts from a new polyurethane elastomer and tailored the grafts' interconnected pore sizes to promote macrophage populations with a pro-regenerative phenotype and improve vascular regeneration and patency rate. The synthetic vascular grafts showed similar mechanical properties to native blood vessels, encouraged macrophage populations with varying M2 to M1 phenotypic expression, and maintained patency and vascular regeneration in a one-month rat carotid interposition model and in a four-month rat aortic interposition model. This innovative bioactive synthetic vascular graft holds promise to treat clinical vascular diseases.

Microwave freeze drying (MFD) can be the rapid removal of water from vegetables and fruits. The quality of dried products can be almost identical to that of conventional freeze drying (FD). MFD can also be expected to potentially replace the conventional FD, particularly for the low cost. However, the excessive local high temperature can result in the local coking during MFD, which has failed to be effectively controlled until now. The excessive local high temperature has restricted the wide range of applications of MFD. In this study, micro-computed tomography (CT) was used to visualize the pore distribution of dried Chinese yam under different microwave loading levels and cavity pressure. A systematic analysis was implemented to determine the pore size and distribution in every partial specimen. The heat and mass transfer mechanism was given for the uneven distribution of temperature during MFD, even for the excessive local temperature. A series of numerical simulations was then carried out to verify the pore size and pore distribution of the structure model. The results indicated that the operation conditions (such as microwave loading level and cavity pressure) shared a significant effect on the pore characteristics of Chinese yam under MFD. There was a distinct distribution in the thickness of the sarcocarp, as the cavity pressure changed. The percentage of 10-50 μm sarcocarp under 200 Pa was higher than that under 100 and 300 Pa. while the percentage of 60-160 μm sarcocarp under 200 Pa was lower than that under 100 and 300 Pa. Low microwave loading level tended to form the small pores, whereas, the large pores were observed at high microwave loading level. Low cavity pressure and microwave loading levels tended to form the much smaller pores. The low microwave loading level also induced the smaller pores with a size between 50 and 160 μm. Meanwhile, the high microwave loading level tended to produce much larger pores with sizes between 200 and 550 μm. There was a significant effect of cavity pressure on the pore size and distribution in the inner specimen, whereas, there was no effect in the outer specimen. Therefore, the larger pore was more prone to form in the middle of the sample during MFD. There was a distinct effect of microwave loading level on the pore size and distribution in both the inner and outer layers. The microwave loading level was prone to produce sudden variation in the pore distribution when the pore size was larger than 800 μm. Compared with the cavity pressure, the microwave loading level can be more likely to change the pore size and pore distribution from the inside out, where a lot of large pores were formed in the inner specimen with a size of larger than 800 μm. The finding can also offer experimental support to the numerical simulation for the local high temperature in MFD. [ABSTRACT FROM AUTHOR]

In this paper, three different fracturing fluids are used as replacement working fluids, and nuclear magnetic resonance technology is used to study the oil-water replacement law of tight sandstone cores in the field, revealing the main influencing factors of oil-water replacement in the process of tight oil fracturing flow back. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The employment of 2-deoxyribose-5-phosphate aldolase (DERA) stands as a prevalent biocatalytic route for synthesizing statin side chains. The main problem with this pathway is the low stability of the enzyme. In this study, mesocellular silica foam (MCF) with different pore sizes was used as a carrier for the covalent immobilization of DERA. Different functionalizing and activating agents were tested and kinetic modeling was subsequently performed. The use of succinic anhydride as an activating agent resulted in an enzyme hyperactivation of approx. 140%, and the stability almost doubled compared to that of the free enzyme. It was also shown that the pore size of MCF has a decisive influence on the stability of the DERA enzyme. [ABSTRACT FROM AUTHOR]

AbstractThe separator membrane is one of the four key materials of a lithium-ion battery, and the size of the separator membrane pores plays an important role on the internal resistance and safety of the battery. In this study, firstly, the relationship between the average pore size and the pore center to center distance with different porosity ratios in the separator membrane was analyzed with statistical theory. Then, a mathematical model was established to predict the probability of intersections and merging of the pores. In the end, the probability of intersections of pores with different porosity ratios were calculated and simulated; the differences between the results obtained from the two ways were 1.16%, 1.47% and 4.16%, when the porosity ratios were 21.36%, 40.16% and 53.34%, respectively, which indicated that the prediction model had good accuracy. [ABSTRACT FROM AUTHOR]

The Stöber method provides a facile procedure for making carbon spheres with controlled particle sizes and is considered to be low-cost. In this study, a facile method has been established for synthesizing porous carbon spheres with variable pore sizes using a modified Stöber process. The influence of acid treatment and manipulating the carbonization process heating rate on the pore size and morphology of the particles was investigated by nitrogen adsorption, Scanning Electron Microscopy (SEM), Powder X-ray diffraction (XRD), Raman and Fourier Transform Infrared Spectroscopy (FTIR). According to the results, carbon spheres were in the size range between 1 and 7 microns. Pore size characterization shows that the pore diameter has increased by increasing the heating rate as well as by performing acid treatment. Tunable pore sizes from 2.25 to 8 nm have been evidenced by the experiments. These synthesized mesoporous carbons with different pore sizes which facilitate penetration of molecules and ions are promising as effective materials for adsorption, encapsulation and material delivery applications. [ABSTRACT FROM AUTHOR]

Concrete gets exposed to weathering. Thus, the structures sustain significant damage, significantly reducing the concrete's durability properties. Nanofillers can improve a material's ability to hydrate, which enhances the material's fresh, toughened and durability assets. The presented work is cement mortar with Ordinary Portland Cement with 10% Ultrafine slag (UFS) and various Graphene oxide (GO) mixtures (0.01% to 0.04%) subjected to 3% sulphuric acid to assess their chemical resistance. The Brunauer, Emmett and Teller analysis appraised the preliminary research by exposing the surface attributes and pore size dimensions. The test result elucidates GO 0.03% with 10% UFS was best. The evaluation of acid-exposed specimens is based on changes in the specimens' size, mass and visual scrutiny. The highest sulphate and acid resistance were observed for CMS4 and CMA4 with the least mass, length and flexure strength loss at 28 and 56 days. The surface was unaffected in microscopic studies, and there was no loss of flexural strength. [ABSTRACT FROM AUTHOR]

Vacuum membrane distillation (VMD) is an intriguing technique that has the potential to separate ethanol from an ethanol–water mixture. The goal of this work was to synthesize hydrophobic polyvinylidene fluoride–polytetrafluoroethylene (PVDF–PTFE) hybrid membranes that could be used in VMD. For membrane synthesis via phase inversion, the outcomes of different solvents, namely N-methyl-2-pyrrolidone (NMP), N,N-dimethyl acetamide (DMAc), and dimethylformamide (DMF), as well as PTFE loading in PVDF dope solution were also evaluated. The desired membrane hydrophobicity was ensured by increasing contact angle from 69° to 135°. The obtained average maximum pore size fell between 0.19 μm and 0.22 μm. Plenty of work has been done on how the performance of the synthesized membrane depends on the VMD operating parameters (ethanol concentration, flow rate, feed temperature, and permeate pressure). The highest separation factor of 37.68 was offered by the membrane synthesized using DMF as a solvent, while the membrane synthesized with the help of DMAc solvent had the most increased ethanol flux of 10.55 kg m−2 h−1. A thorough report has been made on understanding membrane morphologies and VMD performance. [ABSTRACT FROM AUTHOR]

This study presents an integrated approach to understanding fluid dynamics in Microfluidic Paper-Based Analytical Devices (µPADs), combining empirical investigations with advanced numerical modeling. Paper-based devices are recognized for their low cost, portability, and simplicity and are increasingly applied in health, environmental monitoring, and food quality analysis. However, challenges such as lack of flow control and the need for advanced detection methods have limited their widespread adoption. To address these challenges, our study introduces a novel numerical model that incorporates factors such as pore size, fiber orientation, and porosity, thus providing a comprehensive understanding of fluid dynamics across various saturation levels of paper. Empirical results focused on observing the wetted length in saturated paper substrates. The numerical model, integrating the Highly Simplified Marker and Cell (HSMAC) method and the High Order accuracy scheme Reducing Numerical Error Terms (HORNET) scheme, successfully predicts fluid flow in scenarios challenging for empirical observation, especially at high saturation levels. The model effectively mimicked the Lucas–Washburn relation for dry paper and demonstrated the increasing time requirement for fluid movement with rising saturation levels. It also accurately predicted faster fluid flow in Whatman Grade 4 filter paper compared with Grade 41 due to its larger pore size and forecasted an increased flow rate in the machine direction fiber orientation of Whatman Grade 4. These findings have significant implications for the design and application of µPADs, emphasizing the need for precise control of fluid flow and the consideration of substrate microstructural properties. The study's combination of empirical data and advanced numerical modeling marks a considerable advancement in paper-based microfluidics, offering robust frameworks for future development and optimization of paper-based assays. [ABSTRACT FROM AUTHOR]

The commercialized lithium‐ion battery separators are mass‐produced by mixing ultra‐high molecular weight polyethylene (UHMWPE) and paraffin oil (PO). The dissipative particle dynamics method is utilized to investigate the extrinsic factors (shear rate and cooling rate) and the intrinsic factors (the molecular chain length) on the microstructure of the UHMWPE‐PO mixture. For the mixture with UHMWPE possessing the same chain length, the high shear rate promoted a lower porosity (~28%) and smaller pores. In contrast, the slow shearing led to a high porosity (~40%) and larger pores. For the mixture with UHMWPE possessing short and long chains, the shear rate hardly affects the porosity and the pore size: the porosity was kept at ~30%, and the pore size was reduced by ~35% compared to the model with the same‐chain‐length UHMWPE. The cooling rate after shearing is the dominant factor in determining the porosity and pore size: the fast cooling raised the porosity by ~33% but hardly increased the pore size, while the slow cooling raised the porosity by ~74%, and the pore size by ~105%. The current study provided a deep understanding of the pore structure evolution in separator processing. Highlights: The effects of processing parameters on the pore structures are numerically illustrated.MD simulation and rheometer measurement assist DPD interaction parameters calibration for UHMWPE and PO.The low shear rate leads to a higher porosity and pore size.At the high shear rate, short UHMWPE chains reduce porosity but do not increase pore size.The fast‐cooling process slightly increases the porosity while keeping the pore size. [ABSTRACT FROM AUTHOR]

The drying kinetics of porous media are crucial for controlling the drying process, which is a vital component in many processes. A mathematical model of the drying process in a granular bed was developed using Whitaker's model, and its accuracy was verified through experimental results. The results indicated that the three stages of porous media drying are closely linked to the heat flow to the media and the latent heat of evaporation required by the liquid water inside it. Moreover, as the influence of gravity weakens and the capillary force strengthens, specifically due to the gradual decrease in the pore size of the bed, significant differences in the drying kinetics of the bed are observed, particularly in the third stage of drying, which is most affected. The onset of saturation in the third stage of bed drying varies with the pore size of the particles, with smaller pore sizes exhibiting an earlier onset. Additionally, the temperature change in this stage demonstrates the occurrence of secondary warming as the pore size decreases. [ABSTRACT FROM AUTHOR]

Dry explosion (DE), a thermal–mechanical method based on explosive power, was introduced for pretreatment of biomass material. The effects of different dehydration combined with DE pretreatments (120, 140, and 160 °C) on color, pore characteristics, crystallinity, and enzymatic hydrolysis of hybrid Pennisetum (HP) were analyzed. The results showed that dewatering press (PD) removed more soluble substrate in HP than oven drying dehydration (OD). The instantaneous explosive decompression of the DE process significantly increased the explosion power density with the increasing severity factor and reached 45.50 MW·m−3 at 160 °C. Moreover, dehydration combined with DE pretreatment broke the pore structure and destructed cellulose crystallization of HP. Also, it improved the cellulose accessibility and the surface exposure of cellulose, which enhanced the enzymatic hydrolysis yield. PD combined with 160 °C DE promoted the reducing sugar yield of HP to 443.0 mg/g and enzymatic hydrolysis to 70.2%. The correlation analysis showed that reducing sugar yield was significantly correlated with color L* and b* values, surface area, and crystal size. All in all, DE pretreatment is a green and effective method for biomass saccharification utilization. [ABSTRACT FROM AUTHOR]

The influence of pore structure evolution in compacts sintered from nickel carbonyl powder with an average particle size of 1.4 μm in the temperature range 200–1000°C on local and bulk shrinkage was analyzed. The pore structure of the samples was characterized by the maximum and average diameters of pore channel constrictions determined by the Barus–Bechhold method. To minimize local (incoherent) shrinkage in the sintering of fine nickel powders, a criterion for pore structure homogeneity in compacts, α ≤ 0.03, was selected. The criterion was determined by the difference between the maximum and average diameters of pore channel constrictions. The influence of pore structure evolution on local and bulk shrinkage during sintering of compacts produced from nickel carbonyl powder with an average particle size of 1.4 and 4 μm was experimentally confirmed. The local shrinkage was due to the three-level structure and wide particle size distribution of the nickel carbonyl powders. A method was proposed to determine the average diameter of particles (agglomerates) in nickel carbonyl powders using the Kozeny equation, establishing a relationship between the particle diameter, the maximum diameter of pore channel constrictions, and the porosity of the compacts, varying from 0.25 to 0.45. [ABSTRACT FROM AUTHOR]

Although the working principles of capillary barrier effects (CBEs) have been well explained based on unsaturated soil mechanics, the selection of materials for engineering structures with CBEs mostly relies on designers' experience or previously reported data, largely due to the lack of understanding of the microscale behavior of CBEs. This study explores the impact of pore sizes on CBEs based on pore network modeling. The results indicate that the pore size variability in either the fine or coarse layer has a remarkable influence on CBEs, with the latter having a dominating influence. A larger coarse-to-fine mean pore size ratio results in more effective CBEs. In addition to selecting materials with more uniform pore sizes, the coarse-to-fine mean pore size ratio is recommended to be >6 (median particle size ratio of 30) to ensure the performance of CBEs. [ABSTRACT FROM AUTHOR]

The objective of this work is to investigate adsorption separation of liquid‐phase xylene isomers using ultramicroporous carbon spheres. The synthesized glucose‐based adsorbent (UMC‐xyl) enabled the challenging separation of liquid‐phase p‐xylene/m‐xylene with an adsorption selectivity of 53 as well as p‐xylene uptake of 91mg/g, outperforming a series of commercial adsorbents including the industrial benchmark KBaX. The micropore diffusion model was used to give the best fit to the adsorption kinetics of UMC‐xyl with a rate achieved higher than KBaX. The xylene isomer separation was facilitated by the narrow ultramicropore size distributed at 5.8–6.8 Å in UMC‐xyl via a synergistic kinetic and size‐sieving separation mechanism. Breakthrough experiments confirmed the effectiveness of UMC‐xyl in the dynamic selective separation of p‐xylene from xylene isomers, together with superior multiple‐cycle eluent regenerability under the synergistic effects of the "like‐dissolve‐like" principle and π–π interaction. The work opens a new direction of using porous carbon adsorbents for continuous liquid‐phase separation of challenging hydrocarbon isomers. [ABSTRACT FROM AUTHOR]

The highly active and selective oxygen reduction reaction (ORR) is vital to promote the performance of advanced energy conversion systems, such as fuel cells and other electrochemical devices. Porous framework materials have the capability to combine the catalytic performance of catalytic active units with their porous characteristics, making them promising oxygen reduction catalysts. However, due to the difficulty in designing and synthesizing catalytic active units, the pore size modulation of framework materials is primarily achieved by altering the linkers. We herein report the design and synthesis of three cobalt-corrole-based porous organic polymers (Co-POP-1, Co-POP-2 and Co-POP-3) with different pore sizes, which were obtained by extending 5,15-meso substituents of Co corroles. Compared to Co-POP-1 and Co-POP-2, Co-POP-3 has the largest pore size. Benefiting from the enhanced mass transfer and the highly exposed active sites, Co-POP-3 displayed remarkably boosted activity for the selective four-electron/four-proton (4e−/4 H+) ORR with a half-wave potential of E1/2 = 0.89 V versus reversible hydrogen electrode (RHE) in 0.1 M KOH solutions. This work not only presents a cobalt-corrole-based porous organic polymer catalyst with high ORR activity and selectivity but also provides a new strategy to moderate the pore size of porous framework materials.

The effects of pore size in additively manufactured biodegradable porous magnesium on the mechanical properties and biodegradation of the scaffolds as well as new bone formation have rarely been reported. In this work, we found that high temperature oxidation improves the corrosion resistance of magnesium scaffold. And the effects of pore size on the mechanical characteristics and biodegradation of scaffolds, as well as new bone formation, were investigated using magnesium scaffolds with three different pore sizes, namely, 500, 800, and 1400 μm (P500, P800, and P1400). We discovered that the mechanical characteristics of the P500 group were much better than those of the other two groups. In vitro and in vivo investigations showed that WE43 magnesium alloy scaffolds supported the survival of mesenchymal stem cells and did not cause any local toxicity. Due to their larger specific surface area, the scaffolds in the P500 group released more magnesium ions within reasonable range and improved the osteogenic differentiation of bone mesenchymal stem cells compared with the other two scaffolds. In a rabbit femoral condyle defect model, the P500 group demonstrated unique performance in promoting new bone formation, indicating its great potential for use in bone defect regeneration therapy.

The placement of a polymeric electrospun scaffold is among the most promising strategies to improve nerve regeneration after critical neurotmesis. It is of great interest to investigate the effect of these structures on Schwann cells (SCs), as these cells lead nerve regeneration and functional recovery. The aim of this study was to assess SC viability and morphology when cultured on polyhydroxybutyrate (PHB) electrospun scaffolds with varied microfiber thicknesses and pore sizes. Six electrospun scaffolds were obtained using different PHB solutions and electrospinning parameters. All the scaffolds were morphologically characterized in terms of fiber thickness, pore size, and overall appearance by analyzing their SEM images. SCs seeded onto the scaffolds were analyzed in terms of viability and morphology throughout the culture period through MTT assay and SEM imaging. The SCs were cultured on three scaffolds with homogeneous smooth fibers (fiber thicknesses: 2.4 μm, 3.1 μm, and 4.3 μm; pore sizes: 16.7 μm, 22.4 μm, and 27.8 μm). SC infiltration and adhesion resulted in the formation of a three-dimensional network composed of intertwined fibers and cells. The SCs attached to the scaffolds maintained their characteristic shape and size throughout the culture period. Bigger pores and thicker fibers resulted in higher SC viability. [ABSTRACT FROM AUTHOR]

A novel, simple, and rapid method is demonstrated for measuring the pore size and pore size distribution of filtration membranes (FMs) used in aqueous applications with fluorescence probes. Because the selected fluorescent probes are mixable and have strong signals, combined with the operation of dead-end filtration, this method only requires small amounts of reagents; additionally, it is time-efficient by avoiding multiple rounds of filtration. This method detects the size of a FM pore throat (i.e., the narrowest position of a pore tunnel), which is more consistent with the actual filtration situation. The conditions, such as probe concentration, temperature, transmembrane pressure difference, and types of surfactants, have been optimized. The experimental results show that the fluorescence probe method has good accuracy and reproducibility for measuring the pore size and pore size distribution of both organic and inorganic FMs. The method is particularly suitable for rapid testing of the filtration performance (nominal pore size≥0.02 μm) of purchased or synthetic membranes in the laboratory. [ABSTRACT FROM AUTHOR]

Natural tuff samples in western Anatolia (Türkiye) originating from Miocene rhyolitic–pyroclastic rocks with >80 wt.% heulandite/clinoptilolite zeolites were investigated for their surface characteristics determined according to nitrogen adsorption after degassing at 150°C (specific surface area, pore volume and pore diameter). Additionally, these surface characteristics were correlated with the cationic compositions of the heulandite/clinoptilolite group minerals. The examined samples were characterized by two main pore diameters that were not related to specific surface area and pore volume but were partially related to the types and occupancy of extra-framework cations. One set of samples has a pore diameter of ~24 Å, total cation content (Na + K + Ca + Mg) ranging from 3.46 to 4.40 and a (Na + K)/(Ca + Mg) ratio ranging from 0.34 to 0.92. The total cation contents and (Na + K)/(Ca + Mg) ratios of the remaining samples with a pore diameter of ~37 Å are 4.30–5.08 and 1.48–2.85, respectively. After degassing at 300°C, there is a slight difference in the pore diameters of these two sets of samples (~37 and 38 Å). The pore sizes of the samples with a (Na + K)/(Ca + Mg) ratio < 1 (heulandite composition) increased from 24 to 36–38 Å with increasing degassing temperature, whereas the pore sizes of the samples with a (Na + K)/(Ca + Mg) ratio > 1 (clinoptilolite composition) increased from 37 to only 38–39 Å. However, there is no correlation between the Si/Al ratios and the cation-exchange capacities of the samples and their surface characteristics obtained by degassing at the two temperatures. [ABSTRACT FROM AUTHOR]

Background: Pharmacological properties of Quercus infectoria Olivier (galls) have been determined to be astringent, antidiabetic, antipyretic, anti‐tremor, local anesthetic, and anti‐parkinsonism. The galls of Quercus infectoria have been used for millennia in traditional oriental medicine in Asian nations to treat inflammatory illnesses. Aims: The study's objective was to create a Quercus infectoria Olivier gall extract in stable water in oil (w/o) emulsion and to check its effects on the mechanical properties of skin and antiaging effects. Method: The galls were macerated in absolute methanol. Quercus infectoria Olivier gall extract's antioxidant property was evaluated using the 2, 2‐diphenyl‐1‐picrylhydrazyl (DPPH) technique. Stearic acid, cetyl alcohol, KOH, glycerin, and distilled water were used to create the emulsion. The test (with extract) and control (without extract) emulsions were made, respectively, using the same process. Stability tests (color, liquefaction, microscopy, phase separation, and pH) are performed in in vitro, lasted 72 days at four distinct storage temperatures that is 8°C, 25°C, 40°C, and 40°C + 75% RH for both the control and test formulations. By using spectrophotometry, the (SPF) sun protection factors of the two formulations were calculated at various concentrations. Extract from Quercus infectoria underwent phytochemical investigation as well. Results: The results showed that Quercus infectoria Olivier has antioxidant and (SPF) sun protection properties, reduce sebum, increases elasticity and stable emulsion containing 04% Quercus infectoria gall extract which might be used as topical antiaging formulation. [ABSTRACT FROM AUTHOR]

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