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Membrane‐based gas separation offers notable energy efficiency benefits for hydrogen purification, yet it is often hindered by the inherent trade‐off between permeability and selectivity. To address this challenge, a novel mixed matrix membrane (MMM) design is presented to boost H2 separation performance via continuous hydrogen spillover mechanisms for the first time. The MMM incorporates a palladium‐functionalized ZIF‐67 gel (Pd@ZIF‐67 gel) network into a polymer of intrinsic microporosity (PIM‐1) matrix. The ZIF‐67 gel network serves as a uniform dispersion medium for palladium nanoparticles (Pd NPs), thereby generating a multitude of active sites. These exposed sites, in conjunction with the microporous structure of ZIF‐67, facilitate hydrogen dissociation and establish a continuous hydrogen spillover pathway throughout the membrane. This synergistic MMM design leads to substantial improvements in both hydrogen transport and selectivity. At an optimal loading of 28 wt% Pd@ZIF‐67 gel, the MMMs exhibit a H2 permeability of 3620 Barrer and a remarkable 417% enhancement in H2/CH4 selectivity (24.9), surpassing the 2008 upper bound. This approach paves the way for the development of advanced materials tailored for gas separation applications. [ABSTRACT FROM AUTHOR]

Summary: Texture is a multi‐parameter attribute and one of the prime quality attributes of fried products. This study explored the nexus between microstructure and texture of fried breaded chicken nuggets. Chicken nuggets were deep‐fat fried (2, 4, 6, and 8 min) in canola oil at different frying temperature (170, 180, and 190 °C). Microstructure and texture of fried samples were assessed by scanning electron microscopy (SEM) and acoustic‐mechanical texture analyser, respectively. Maximum force (Fmax), number of force peaks (NFP), area under force‐deformation plots (FA), sound pressure level (SPL), number of sound peaks (AUX), and area under amplitude‐time curves (SA) were used to describe the textural parameters. Microstructural indices (porosity, number of pores, average pore area, polydispersity index, and average shape factor) were estimated from the SEM images. Results revealed that, both the frying time and temperature were positively correlated with the mechanical (Fmax: 25–55 N, NFP: 05–74 N, FA: 6500–15 000 N.sec) and acoustic (SPL: 88–97 dB, AUX: 650–810 dB, SA: 380–405 dB.sec) parameters. Frying time and temperature significantly (P < 0.05) impacted the formation of micropores in fried chicken nuggets. Crust microporosity showed strong positive correlations (r = 0.82) with the AUX value. The NFP, SPL, and SA of the fried nuggets were significantly (P < 0.05) impacted by the crust microporosity. Crust porosity (10–30%), number of pores (8–400), average pore area (10–4000 μm2), polydispersity index (0.05–0.2), and average shape factor (0.8–1.1) of fried nuggets were significantly (P < 0.05) influenced by both the frying time and temperature. Findings from this study would be useful in quality improvement and process monitoring including modelling of coated fried products. [ABSTRACT FROM AUTHOR]

Microbubbles (MB) are widely used as contrast agents for ultrasound (US) imaging and US‐enhanced drug delivery. Polymeric MB are highly suitable for these applications because of their acoustic responsiveness, high drug loading capability, and ease of surface functionalization. While many studies have focused on using polymeric MB for diagnostic and therapeutic purposes, relatively little attention has thus far been paid to improving their inherent imaging and drug delivery features. This study here shows that manipulating the polymer chemistry of poly(butyl cyanoacrylate) (PBCA) MB via temporarily mixing the monomer with the monomer‐mimetic butyl cyanoacetate (BCC) during the polymerization process improves the drug loading capacity of PBCA MB by more than twofold, and the in vitro and in vivo acoustic responses of PBCA MB by more than tenfold. Computer simulations and physisorption experiments show that BCC manipulates the growth of PBCA polymer chains and creates nanocavities in the MB shell, endowing PBCA MB with greater drug entrapment capability and stronger acoustic properties. Notably, because BCC can be readily and completely removed during MB purification, the resulting formulation does not include any residual reagent beyond the ones already present in current PBCA‐based MB products, facilitating the potential translation of next‐generation PBCA MB. [ABSTRACT FROM AUTHOR]

Porous titanium addresses the longstanding orthopedic challenges of aseptic loosening and stress shielding. This work expands on the evolution of porous Ti with the manufacturing of hierarchically porous, low stiffness, ductile Ti scaffolds via direct-ink write (DIW) extrusion and sintering of inks containing Ti and NaCl particles. Scaffold macrochannels were filled with a subtherapeutic dose of recombinant bone morphogenetic protein-2 (rhBMP-2) alone or co-delivered within a bioactive supramolecular polymer slurry (SPS) composed of peptide amphiphile nanofibrils and collagen, creating four treatment conditions (Ti struts: microporous vs. fully dense; BMP-2 alone or with SPS). The BMP-2-loaded scaffolds were implanted bilaterally across the L4 and L5 transverse processes in a rat posterolateral lumbar fusion model. In-vivo bone growth in these scaffolds is evaluated with synchrotron X-ray computed microtomography (µCT) to study the effects of strut microporosity and added biological signaling agents on the bone formation response. Optical and scanning electron microscopy confirms the ∼100 µm space-holder micropore size, high-curvature morphology, and pore fenestrations within the struts. Uniaxial compression testing shows that the microporous strut scaffolds have low stiffness and high ductility. A significant promotion in bone formation was observed for groups utilizing the SPS, while no significant differences were found for the scaffolds with the incorporation of micropores. By 2050, the anticipated number of people aged 60 years and older worldwide is anticipated to double to 2.1 billion. This rapid increase in the geriatric population will require a corresponding increase in orthopedic surgeries and more effective materials for longer indwelling times. Titanium alloys have been the gold standard of bone fusion and fixation, but their use has longstanding limitations in bone-implant stiffness mismatch and insufficient osseointegration. We utilize 3D-printing of titanium with NaCl space holders for large- and small-scale porosity and incorporate bioactive supramolecular polymers into the scaffolds to increase bone growth. This work finds no significant change in bone ingrowth via space-holder-induced microporosity but significant increases in bone ingrowth via the bioactive supramolecular polymers in a rat posterolateral fusion model. [Display omitted] [ABSTRACT FROM AUTHOR]

Barium titanate (BTO) is well-known (as a photo- or sono/piezo-catalyst) to produce hydrogen peroxide via 2-electron reduction of oxygen in the presence of a sacrificial quencher, such as isopropanol. While barium titanate nanoparticles with a tetragonal crystal structure (piezoelectric) are particularly reactive, the recovery and reuse of these nano-catalysts from reactions can be difficult. Here, barium titanate nanoparticles of typically 200 nm to 600 nm diameter are embedded into a host film of a polymer of intrinsic microporosity (PIM-EA-TB). Due to molecular rigidity of the polymer, there is no capping effect, and the surface catalytic reaction occurs effectively with a catalyst embedded in the polymer. In this exploratory work, the catalytic formation of H2O2 in the presence of isopropanol is investigated via kinetic studies and by electron paramagnetic resonance (EPR). Perhaps surprisingly, at a neutral pH the rate of the catalytic reaction is substantially increased when barium titanate is embedded into the polymer host and when the polymer is protonated. This is attributed here to a "kinetic cage effect" which exploits the tertiary amine in the polymer backbone with anodic and cathodic processes coupled into a pH neutral reaction. [ABSTRACT FROM AUTHOR]

In sharp contrast to numerous artificial potassium channels developed over the past decade, the study of artificial lithium‐transporting channels has remained limited. We demonstrate here the use of an interesting class of polymers with intrinsic microporosity (PIM) for constructing artificial lithium channels. These PIM‐derived lithium channels show exceptionally efficient (γLi+>40 pS) and highly selective transport of Li+ ions, with selectivity factors of>10 against both Na+ and K+. By simply adjusting the initial reaction temperature, we can tune the transport property in a way that PIMs synthesized at initial reaction temperatures of 60 °C and 80 °C exhibit improved transport efficiency and selectivity, respectively, in the dioleoyl phosphatidylcholine membrane. [ABSTRACT FROM AUTHOR]

In this study, inexpensive dual precursors namely rice husk ash (RHA) and quarry dust (QD) were mixed with an alkali solution (NaOH solution) in different mix proportions. Next, the effect of the dual precursors-alkali solutions (geopolymers) on the strength parameters of the different soil-geopolymer mixes subjected to various curing days were assessed. The result obtained from the assessment showed that the dual precursors-alkali solutions improved the strength properties of all the different soil-geopolymer mixes. The optimum soil-geopolymer mix proportion that resulted in the best improvement of the expansive subgrade soil properties was observed at a combination of 15%RHA+15%QD+3M NaOH. Furthermore, micro-pore analyses (porosity and pore size distribution), which were implemented with scanning electron micrographs and an image segmentation technique, local adaptive thresholding algorithm, showed progressive reduction in the porosity of the natural expansive subgrade soil and that of the optimal soil-geopolymer mix proportion cured for 7 and 28 days. [ABSTRACT FROM AUTHOR]

Ion exchange membranes (IEMs) play a critical role in aqueous organic redox flow batteries (AORFBs). Traditional IEMs that feature microphase‐separated microstructures are well‐developed and easily available but suffer from the conductivity/selectivity tradeoff. The emerging charged microporous polymer membranes show the potential to overcome this tradeoff, yet their commercialization is still hindered by tedious syntheses and demanding conditions. We herein combine the advantages of these two types of membrane materials via simple in situ hypercrosslinking of conventional IEMs into microporous ones. Such a concept is exemplified by the very cheap commercial quaternized polyphenylene oxide membrane. The hypercrosslinking treatment turns poor‐performance membranes into high‐performance ones, as demonstrated by the above 10‐fold selectivity enhancement and much‐improved conductivities that more than doubled. This turn is also confirmed by the effective and stable pH‐neutral AORFB with decreased membrane resistance and at least an order of magnitude lower capacity loss rate. This battery shows advantages over other reported AORFBs in terms of a low capacity loss rate (0.0017 % per cycle) at high current density. This work provides an economically feasible method for designing AORFB‐oriented membranes with microporosity. [ABSTRACT FROM AUTHOR]

This study examines the corrosion characteristics of weakly cemented sandstone under alkaline conditions, evaluating the effects of varying pH levels on its macroscopic degradation, micro-porosity, and mechanical properties, notably uniaxial compressive strength. Findings reveal that heightened alkalinity exacerbates rock damage, although a temporary alleviation in mass loss occurs between pH 9 and 11 due to pore clogging by complexes formed from cations like Ca2+ and Mg2+.Increased alkalinity induces marked changes in pore features, with an observed rise in pore numbers, transformation of pore shapes from elongated to more spherical, and adjustments in porosity, pore size, and roundness. Furthermore, the study confirms a decline in both the rock's compressive strength and elastic modulus as pH rises. These revelations shed light on the role of pH in the corrosion behavior of weakly cemented sandstone under alkaline conditions, providing a fresh perspective for understanding its corrosion mechanisms in such environments. [ABSTRACT FROM AUTHOR]

A viable tactic to effectively address the climate crisis is the production of renewable fuels via photocatalytic reactions using solar energy and available resources like carbon dioxide (CO2) and water. Organic polymer material-based photocatalytic materials are thought to be one way to convert solar energy into valuable chemicals and other solar fuels. The use of porous organic polymers (POPs) for CO2 fixation and capture and sequestration to produce beneficial compounds to reduce global warming is still receiving a lot of interest. Visible light-responsive organic photopolymers that are functionally designed and include a large number of heteroatoms and an extended π-conjugation allow for the generation of photogenerated charge carriers, improved absorption of visible light, increased charge separation, and decreased charge recombination during photocatalysis. Due to their rigid structure, high surface area, flexible pore size, permanent porosity, and adaptability of the backbone for the intended purpose, POPs have drawn more and more attention. These qualities have been shown to be highly advantageous for numerous sustainable applications. POPs may be broadly categorized as crystalline or amorphous according to how much long-range order they possess. In terms of performance, conducting POPs outperform inorganic semiconductors and typical organic dyes. They are light-harvesting materials with remarkable optical characteristics, photostability, cheap cost, and low cytotoxicity. Through cocatalyst loading and morphological tweaking, this review presents optimization options for POPs preparation techniques. We provide an analysis of the ways in which the preparative techniques will affect the materials' physicochemical characteristics and, consequently, their catalytic activity. An inventory of experimental methods is provided for characterizing POPs' optical, morphological, electrochemical, and catalytic characteristics. The focus of this review is to thoroughly investigate the photochemistry of these polymeric organic photocatalysts with an emphasis on understanding the processes of internal charge generation and transport within POPs. The review covers several types of amorphous POP materials, including those based on conjugated microporous polymers (CMPs), inherent microporosity polymers, hyper-crosslinked polymers, and porous aromatic frameworks. Additionally, common synthetic approaches for these materials are briefly discussed. [ABSTRACT FROM AUTHOR]

Abstract The one-step carbonization of low cost and abundant chitosan biopolymer in the presence of salt eutectics ZnCl2/NaCl results in nitrogen-doped carbon nanostructures (8.5 wt.% total nitrogen content). NaCl yields the spacious 3D structure, which allows external oxygen to easily reach the active sites for the oxygen reduction reaction (ORR) distinguished by their high onset potential and the maximum turnover frequency of 0.132 e site⁻1 s⁻1. Data show that the presence of NaCl during the synthesis exhibits the formation of pores having large specific volumes and surface (specific surface area of 1217 m2 g−1), and holds advantage by their pores characteristics such as their micro-size part, which provides a platform for mass transport distribution in three-dimensional N-doped catalysts for ORR. It holds benefit over sample pre-treated with LiCl in terms of the micropores specific volume and area, seen as their percentage rate, measured in the BET. Therefore, the average concentration of the active site on the surface is larger.

[Display omitted] Despite significant research into cellulose nanofibril (CNF) films as substitutes to synthetic plastic materials, commercial applications remain very limited. One major hindrance is the poor water vapor barrier properties of CNF films compared to polyolefins, a critical property for product protection, such as food safety and preservation. To date, it is unknown whether full moisture barrier properties can be achieved with materials made by the assembly of nanofibers and fibrils. A comprehensive understanding of the effect of film structure on water vapor transport properties is required. Here, over 200 films were produced with a wide range of grammages from 30 g/m2 to 580 g/m2 by casting and spray deposition. Their structures were quantified by µCT and SEM and related to their water vapor transmission rates (WVTRs). Porosity and pore connectivity decreased with increasing film grammage, which correlates with the exponential decrease in WVTR. However, the WVTR plateaued at 30 g/m2day, indicating that the known open space and adsorption diffusion mechanisms cannot be fully eliminated by producing high grammage films. Pure cellulose nanofibril films therefore cannot replace polyolefins in packaging applications, requiring modifications such as coating and nanofillers. [ABSTRACT FROM AUTHOR]

We here review mostly experimental and some computational work devoted to nucleation in amorphous ices. In fact, there are only a handful of studies in which nucleation and growth in amorphous ices are investigated as two separate processes. In most studies, crystallization temperatures Tx or crystallization rates RJG are accessed for the combined process. Our Review deals with different amorphous ices, namely, vapor-deposited amorphous solid water (ASW) encountered in many astrophysical environments; hyperquenched glassy water (HGW) produced from μm-droplets of liquid water; and low density amorphous (LDA), high density amorphous (HDA), and very high density amorphous (VHDA) ices produced via pressure-induced amorphization of ice I or from high-pressure polymorphs. We cover the pressure range of up to about 6 GPa and the temperature range of up to 270 K, where only the presence of salts allows for the observation of amorphous ices at such high temperatures. In the case of ASW, its microporosity and very high internal surface to volume ratio are the key factors determining its crystallization kinetics. For HGW, the role of interfaces between individual glassy droplets is crucial but mostly neglected in nucleation or crystallization studies. In the case of LDA, HDA, and VHDA, parallel crystallization kinetics to different ice phases is observed, where the fraction of crystallized ices is controlled by the heating rate. A key aspect here is that in different experiments, amorphous ices of different "purities" are obtained, where "purity" here means the "absence of crystalline nuclei." For this reason, "preseeded amorphous ice" and "nuclei-free amorphous ice" should be distinguished carefully, which has not been done properly in most studies. This makes a direct comparison of results obtained in different laboratories very hard, and even results obtained in the same laboratory are affected by very small changes in the preparation protocol. In terms of mechanism, the results are consistent with amorphous ices turning into an ultraviscous, deeply supercooled liquid prior to nucleation. However, especially in preseeded amorphous ices, crystallization from the preexisting nuclei takes place simultaneously. To separate the time scales of crystallization from the time scale of structure relaxation cleanly, the goal needs to be to produce amorphous ices free from crystalline ice nuclei. Such ices have only been produced in very few studies. [ABSTRACT FROM AUTHOR]

In the present work, the impact of hot top geometry and thermal history on the Columnar-to-Equiaxed Transition (CET) point, of a 12 MT steel ingot was determined using finite element modeling. Experimental validation of the model was conducted on an industrial-size ingot, focusing on temperature, macrosegregation, and shrinkage microporosity. The anticipated Columnar-to-Equiaxed Transition point, influenced by the interaction of solid front rate, thermal gradient, and solid fraction was considered in the analysis. The findings revealed a shift in the CET position in new configurations, up to 56 mm, 63 mm, and 60 mm from the ingot wall in the bottom, middle, and top of the ingot, respectively. The changes are attributed to variations in the kinetics of solidification, particularly the solidification time. Thermo-mechanical phenomena, encompassing mold filling, cooling, solutal convection, and flow driven by shrinkage, were incorporated into the model to predict macrosegregation and the risk of porosity and shrinkage cavity formation for different hot top geometries. A criterion is proposed that allows mitigating macrosegregation and minimizing the risk of porosity and shrinkage cavity.

Clay–polymer nanocomposites (CPNs) containing a small weight fraction of nanoclay are known to display enhanced mechanical and thermal properties compared to neat polymers. However, the preparation and application of such nanocomposites remain challenging owing to the difficulties in dispersing nanoclays in polymer matrices. This study focuses on two surfactant-modified organophilic sepiolite clays to demonstrate the simplicity of the modification process, as well as on the use of a benzoxazine monomer (i.e., a CPN matrix precursor) itself as the modifier. Our in-house modified bespoke sepiolites achieve much better dispersion in a benzoxazine matrix, compared to the pristine clay, revealing their potential for applications as nanoenhancers for advanced composites. [ABSTRACT FROM AUTHOR]

Porous boron nitrides (PBN) offer the potential for hydrogen storage, yet struggle to adsorb H 2 even at extremely low temperatures and high pressures due to weak hydrogen binding. Previous studies indicate that doping heteroatoms onto BN substrate enhances its H 2 affinity, but microstructural changes, especially in pore structure, also crucially impact H 2 adsorption. In this study, we synthesized heteroatom-doped porous boron nitrides (HPBN-n-T) by adjusting nitrogen-to-boron source ratios (n) and calcination temperature (T). Comprehensive characterization revealed that heteroatom doping altered both the chemical composition and pore structure of HPBNs. Both heteroatom content and the highest microporosity are the key factors influencing the hydrogen storage performance, but the former and the latter play a more important role at low and room temperatures, respectively. HPBN-3-800 exhibits the strongest affinity for hydrogen (1.05 and 0.87 × 10−3 wt% g m−2) at low temperatures (77 K and 87 K) under 1 bar due to its high heteroatom content (5.56 at%). Meanwhile, HPBN-1-1000 demonstrates the highest affinity for hydrogen (1.18 × 10−3 wt% g m−2) at room temperature (298 K) under 130 bar owing to its highest microporosity (74.5%). In addition, HPBN-3-800 and HPBN-1-1000 also show the highest isosteric heat of adsorption (Q st), 7.55 and 7.53 kJ/mol respectively, confirming that increasing heteroatoms content and microporosity jointly enhance the affinity to hydrogen for HPBNs. DFT calculations further reveal that both heteroatoms and pore defects contribute to generating charge defects to enhance the interaction between the BN substrate and H 2 molecules. This study highlights the effect of heteroatom doping-induced chemical and textural variations on H 2 adsorption and offers insights into designing PBN materials for hydrogen storage via heteroatom doping. [Display omitted] • Heteroatom doping not only affects the chemical composition but also textural properties of HPBNs. • The heteroatom content and microporosity enhance the isosteric heat of adsorption of HPBNs and improve hydrogen storage performance by generating charge defects that enhance the interaction between BN and H 2. • HPBN-3-800, with high heteroatom doping, achieved H 2 uptake per SSA of 1.05 × 10⁻³ wt.% g m⁻2 (77 K, 1 bar), while HPBN-1-1000, with 74.5% microporosity, reached 0.54 × 10⁻³ wt.% g m⁻2 (298 K, 130 bar). [ABSTRACT FROM AUTHOR]

Polymer‐derived ceramics (PDCs) are a class of advanced materials obtained by pyrolysis in a controlled atmosphere of an organosilicon polymer. Their functional as well as mechanical properties originate from the peculiar nanostructures developed during the pyrolysis. Herein, we investigate the formation of transient microporosity in a model PDC (methyl‐silsesquioxane) obtained in Ar, Ar–5%H2, CO2, and air. It is shown that a common evolution can be detected up to 700°C. At this temperature, the structure of the material in terms of chemical bonds is marginally changed (only redistribution reactions take place), but the medium‐range order is clearly modified moving the system to a more disordered state (detected by small angle x‐ray scattering [SAXS]) and causing the formation of a large amount of open micropores sized at about 1.2–1.7 nm. In the 700–800°C range, the proper ceramization starts causing the formation of a new class of small (around 1 nm) open micropores. These partially annihilate at 900°C in Ar and Ar–H2 (i.e., in the second part of the ceramization process), whereas they totally collapse in CO2 due to the formation of a more silica‐like SiOC (less polymerized and viscous). Finally, SAXS points out the persistence of relatively large closed nanovoids of about 1 nm at 1250°C for the samples treated in Ar and Ar–H2. These might explain anomalies in terms of density, elastic modulus, and thermal conductivity of this class of ceramics as reported in the literature. [ABSTRACT FROM AUTHOR]

Numerous efforts in the additive manufacturing literature have been made toward in-situ defect prediction for process control and optimization. However, the current work in the literature is limited by the need for multi-sensory data in appropriate resolution and scale to capture defects reliably and the need for systematic experimental and data-driven modeling validation to prove utility. For the first time in literature, we propose a data-driven neural network framework capable of in-situ micro-porosity localization for laser powder bed fusion via exclusively within hatch strip of sensory data, as opposed to a three-dimensional neighborhood of sensory data. We further propose using prior-guided neural networks to utilize the often-abundant nominal data in the form of a prior loss, enabling the machine learning structure to comply more with process physics. The proposed methods are validated via rigorous experimental data sets of high-strength aluminum A205 parts, repeated k-fold cross-validation, and prior-guided validation. Using exclusively within hatch stripe data, we detect and localize porosity with a spherical equivalent diameter (SED) smaller than 50.00 μ m with a classification accuracy of 73.13 ± 1.57 % This is the first work in the literature demonstrating in-situ localization of porosities as small as 38.12 μ m SED and is more than a five-fold improvement on the smallest SED porosity localization via spectral emissions sensory data in the literature. In-situ localizing micro-porosity using exclusively within hatch-stripe data is a significant step towards within-layer defect mitigation, advanced process feedback control, and compliance with the reliability certification requirements of industries such as the aerospace industry. [ABSTRACT FROM AUTHOR]

Lightweight applications in aerospace and automotive fields generally dictate the joining of dissimilar materials. Such lightweight materials are also finding applications in bio-implant-related applications. This study aims to determine the best possible combination of process parameters to ensure good joints of AZ31B alloy with Ti-6Al-4V alloy sheets. The defects associated with the joints are also discussed in detail. While choosing the level of current for this dissimilar material combination, care should be exercised. A low level of current (50 A) induces problems associated with poor wettability of magnesium, whereas a high current (75 A) leads to the excessive evaporation of magnesium. Macroscopically good-quality joints are processed with a welding current of 60 A and a welding speed of 0.13 m/min. During tensile-shear testing, good quality joints could sustain the ultimate load of 2073 N, while similar joints at the same parameter with microporosities have failed at 985 N. Defect-free joints have exhibited a 110% increase in joint strength when compared with the strength of the joints having microporosities at the interface. [ABSTRACT FROM AUTHOR]

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The implementation of renewable energy sources to electrify ammonia (NH3) production is identified as a critical approach for achieving successful decarburization in the pursuit of a more sustainable future. A liquid metal‐based method is presented for synthesizing bismuth (Bi) nano‐electrocatalysts, enabling efficient and sustainable ammonia production via nitrate electroreduction. Bi‐metal precipitated from a gallium liquid metal alloy yields solution‐processable Bi and oxide with controllable nanostructures such as nanosheets, nanotubes, and nanoparticles. Combining Bi nano‐electrocatalysts and graphene liquid crystals creates self‐assembling layered electrocatalytic systems. Integrating 3D printing technology allows for precise control over the geometry, microporosity, and number of deposited layers of the electrocatalytic scaffold electrode, resulting in improved mass transport properties, durability, and the prevention of catalyst detachment. Consequently, the ammonia production rate reaches 400 nmol s−1 cm−2, with a Faradaic efficiency of over 90% and current densities exceeding 350 mA cm−2. These numbers indicate the excellent scalability potential of the proposed electrocatalytic system. [ABSTRACT FROM AUTHOR]

The permeability for gases through polyurethane (PUR) aerogels prepared from unsorted PUR scraps by means of a recycling technique is measured with a dynamic pressure method. The permeabilities are in the range of 10−15 to 10−13 m2 and thus reflect the pore morphology observed with scanning electron microscopy. The permeability depends on the envelope density and microstructural features of the aerogels and decreases with increasing inner surface area. The comparison of the permeability with the Porod constant, which is obtained independently via small‐angle X‐ray scattering (SAXS), yields a high consistency with the expected theoretical relationship. However, a calculation of inner surface area based on permeability yields lower results than expected from data based on the established SAXS technique, revealing that the famous Carman–Kozeny law correlates only by trend, which is attributed to additional gas transport through the micro‐ and mesopores. A possible approach for the correlation of this behavior to the tortuosity is given. Several models accounting for the combined action of viscous flow, Knudsen diffusion, and molecular slip along pore walls are fitted to the experimental data, effectively qualifying the permeability measurement as time‐efficient and inexpensive technique for the characterization of structural features of aerogels. [ABSTRACT FROM AUTHOR]

Composite metal foams (CMFs) are a new class of closed-cell porous materials that can be produced by distributing metallic spheres in a metallic matrix. CMFs could offer better mechanical performance in comparison to the conventional metal foams due to the uniform shape and even distribution of voids. To evaluate elastic properties of CMFs, the conventional theoretical approaches for periodic models are not good candidates due to the random distribution of voids in these materials. Thus, in this research, first, a three-dimensional model is developed based on the Lubachevsky and Stillinger (LS) approach, which is then used for the FE analysis. Using homogenization technique, the elastic properties of the CMFs are evaluated focusing here on elastic modulus and Poisson's ratio. Comparing results against experimental results shows a very good agreement. In this paper, for the first time, effects of geometrical and material parameters such as thickness of the spheres, microporosity in the wall of spheres and matrix, matrix materials, and diameter of the spheres on the elastic properties of CMFs are examined. It is observed that the microporosity in the matrix has higher effect on the elastic modulus of the CMFs than the microporosity in the wall of the spherical particles. [ABSTRACT FROM AUTHOR]

Heavy metals and their toxicity are a major global concern. They are one of the major environmental problems causing serious problems for living beings. In this study, the adsorption properties of a clay sample located in nature are improved by treating with different materials, and then adsorption properties are examined. It is observed that clay sample can be used in many adsorption applications, including the adsorption of heavy metals such as copper. The clay mineral used in the study was obtained from a rhyolite type rock. Rhyolite rocks, one of the degradation products of volcanic rocks, are the volcanic counterparts of granite. In this study, rhyolite rock was crushed with suitable crushers and grinders, then sieved under 200 mesh with molecular sieve and clay minerals were obtained. The clay samples (K1,K2. K8) were synthesized by subjecting clay with acid and base. Adsorption properties of clay are due to wide surface area, surface functional groups and microporosity. Adsorption of methylene blue and iodine, adsorption from aqueous solutions of copper are done with clay samples and results were compared with samples of clay have not undergone any pre-treatment. In the study, the highest adsorption capacity was determined by applying the Freundlich isotherm. In the K6 sample treated with a base, the highest adsorption capacity was calculated as 26.98 Lg−1. In contrast, the Langmuir isotherm results were calculated in the range of 10.56 to 11.86 Lg−1. This indicates that the adsorption takes place on a heterogeneous surface. The structure and surface properties of clay were examined. [ABSTRACT FROM AUTHOR]

This article studies the shrinkage porosity model for steel ingots with reduction deformation during solidification, and examines the effect of reduction deformation on the shrinkage porosity. Initial investigations involve conducting experiments on reduction deformation during steel ingot solidification, entailing laboratory‐based high‐temperature melting and jack reduction process, with a focus on diverse reduction amounts and cooling times before reduction. Post‐experimental procedures include sample sectioning, acid etching, and low‐magnification structural analysis. Following this, numerical simulations are employed to model the solidification and reduction deformation processes of the steel ingot. Ultimately, a shrinkage porosity criterion model is developed, integrating the equivalent plastic strain resulting from reduction deformation during solidification into the micro‐porosity criterion model. This approach facilitates the prediction of micro‐porosity distribution following reduction deformation. Findings reveal that the shrinkage porosity criterion G2L−5/3ε/εa, which includes the equivalent plastic strain coefficient, effectively predicts the distribution of micro‐porosity subsequent to reduction deformation during steel ingot solidification. A higher reduction amount during the solidification process corresponds to a lowered level of internal micro‐porosity. [ABSTRACT FROM AUTHOR]

Due to their outstanding corrosion resistance, mechanical characteristics and low specific density, AA5083 and AA6061-T6 Al alloys are used in the aerospace, automotive and marine sectors. Joining such dissimilar Al alloys using conventional fusion welding techniques is very challenging. In contrast, laser beam welding (LBW) is a non-conventional welding technique that is promising to weld dissimilar materials. The viability of welding dissimilar AA5083 and AA6061-T6 joints using fibre laser welding are examined herein. The effect of laser power and welding speed on the morphological, microstructural, microhardness and tensile strength of the welded joints was assessed and revealed that increasing welding power resulted in deeper keyhole penetration. Microporosities were formed due to Mg evaporation and shrinkages; however, the existence of these porosities did not show significant effect on the tensile strength. The microhardness values indicate that the welds were harder than the AA6061 and AA5083 base metals. This is explained by the existence of Mg2Si phase in the AA5083-AA6061 dissimilar junction in addition to the grain size circumstances. The fracture examination showed brittle fracture pattern that is regarded to the formation of brittle intermetallic compound (IMC) phases of Mg2Si, in addition to the inter-dendritic brittle phases of other sites as they were frequently inter-granular. [ABSTRACT FROM AUTHOR]

We investigate the fully nonlinear model for convection in a Darcy porous material where the diffusion is of anomalous type as recently proposed by Barletta. The fully nonlinear model is analysed but we allow for variable gravity or penetrative convection effects which result in spatially dependent coefficients. This spatial dependence usually requires numerical solution even in the linearized case. In this work, we demonstrate that regardless of the size of the Rayleigh number, the perturbation solution will decay exponentially in time for the superdiffusion case. In addition, we establish a similar result for convection in a bidisperse porous medium where both macro- and microporosity effects are present. Moreover, we demonstrate a similar result for thermosolutal convection. [ABSTRACT FROM AUTHOR]

Granular type of bone substitutes is currently used in the field of dentistry to restore alveolar bone defects. However, the migration of the granules from the implantation site is still an unresolved issue. In this study, the feasibility to fabricate self-setting calcium sulfate hemihydrate (CSH) granules using different ranges of loading pressure: CSH(0), CSH(50), CSH(100), and CSH(150) was investigated with the hypothesis that CSH granules with reduced microporosity can inhibit the rapid dissolution rate of the calcium sulfate dihydrate (CSD) set blocks and induce bone regeneration. After 4 weeks of implantation, the granules were mostly replaced with new bone although no significant differences were observed. Nevertheless, the granules demonstrated the ability to set within the bone defect. It is therefore concluded that the setting ability of calcium sulfate can contribute to address the issue of migration of the granules and provide a useful guide for designing setting bone substitutes. [ABSTRACT FROM AUTHOR]

In-situ observations of the evolution of hydrogen microporosity nucleation and growth during solidification of Al–Cu–Li alloys were conducted by using synchrotron X-ray radiography. The kinetic behavior of hydrogen microporosity and the mechanisms of nucleation and growth were investigated and verified by comparison with a multiscale model. Hydrogen microporosity was found to nucleate at temperatures between 610 °C and 622 °C during solidification and exhibited rapid growth between 565 °C and 610 °C, with growth rates around 3.2 μm/s. The evolution of hydrogen microporosity growth was best described by the Boltzmann function and displayed merging and ripening behavior. The average equivalent diameter ( D ¯ e ) of hydrogen microporosity and hydrogen supersaturation (SSH) followed the relationship D ¯ e =23.96SSH−0.27. The evolution of 3D hydrogen microporosity during the solidification of Al–Cu–Li alloy was predicted by using a multiscale model. Simulation results agreed well with in-situ experiments, offering a predictive tool for optimizing the manufacturing process of Al–Cu–Li alloy products. [ABSTRACT FROM AUTHOR]

Zeolitic octahedral metal oxide is a newly synthesized all‐inorganic zeolitic material and has been used for adsorption, separation, and catalysis. Herein, a new zeolitic octahedral metal oxide was synthesized and characterized. The porous framework was established through the assembly of [P2Mo13O50] clusters with PO4 linkers. Guest molecules occupied the framework, which could be removed through heat treatment, thereby opening the micropores. The pore characteristics were controlled by the cations within the micropore, enabling the adjustment of the interactions with alkynes and alkenes. This resulted in good separation performance of ethylene/acetylene and propylene/propyne even under high temperature and humidity conditions. The high stability of the material enabled the efficient recovery and reuse without discernible loss in the separation performance. Due to the relatively weak interaction between the adsorbed alkyne and the framework, the adsorbent facilitated the recovery of a highly pure alkyne. This feature enhances the practical applicability of the material in various industrial processes. [ABSTRACT FROM AUTHOR]

Nickel nanoparticle electrodeposition is studied on flat glassy carbon (GC) or on nitrogen‐doped reduced graphene oxide (rGO‐N) substrates. The effects of a very thin (nominally 16 nm) layer polymer of intrinsic microporosity (PIM‐1) are investigated (i) on enhancing nickel nanoparticle nucleation and growth during electrodeposition and (ii) on enhancing hydrogen evolution electrocatalysis. Beneficial effects are tentatively assigned to PIM‐1 suppressing blocking effects from interfacial hydrogen bubble formation. Exploratory data suggest that in aqueous 0.5 M NaCl solution (artificial seawater) nickel nanoparticles grown into a thin film of PIM‐1 could be a viable electrocatalyst with an onset of hydrogen evolution only slightly negative compared to that observed for platinum nanoparticles. [ABSTRACT FROM AUTHOR]

In this paper, we provide a comprehensive review of the latest research trends in terms of the preparation, and characteristics of activated carbons regarding CO2 adsorption applications, with a special focus on future investigation paths. The reported current research trends are primarily closely related to the synthesis conditions (carbonization and physical or chemical activation process), to develop the microporosity and surface area, which are the most important factors affecting the effectiveness of adsorption. Furthermore, we emphasized the importance of regeneration techniques as a factor determining the actual technological and economic suitability of a given material for CO2 capture application. Consequently, this work provides a summary and potential directions for the development of activated carbons (AC). We attempt to create a thorough theoretical foundation for activated carbons while also focusing on identifying and specific statements of the most relevant ongoing research scope that might be advantageous to progress and pursue in the coming years. [ABSTRACT FROM AUTHOR]

Polymer membranes are widely used for gas separation, addressing critical environmental and energy issues. Nevertheless, crafting high‐performance polymer membranes remains a challenging task, often relies on labor‐intensive trial‐and‐error experiments. Different from the traditional Edisonian approach, machine learning offers significant potential to expedite the design of new polymer membranes for gas separation, yet it faces a substantial hurdle due to limited data availability. To overcome this challenge, in this study two physics‐informed performance metrics are introduced, namely fractional free volume and average void size, to assess the separation performance of polymer membranes. By employing active learning and multi‐target screening, top‐performing polyimides with intrinsic microporosity are efficiently discovered from a pool of 155 610 candidates, through calculations of only 709 (0.45%) in the entire search space. As validated by molecular simulations, the top‐performing polyimides exhibit exceptional separation performance for CO2/N2, CO2/CH4, and O2/N2 mixtures, superior to existing polymers and surpassing the current upper bound. The utilization of physics‐informed performance metrics provides a novel strategy to advance the design and accelerate the discovery of new polymer membranes for gas separation and many other important applications. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are networks of metal ions or clusters bonded by organic ligands. Their exceptional micro-porosity and vast surface area make them versatile in various applications. Despite MOFs' extensive potential, much remains unknown regarding their properties and applications across fields. Tunable micro-porosity depends on metal and ligand combinations, but determining the optimal pairings presents challenges. We aim to identify potential optimal candidates, employing graph kernels to study organic ligand structural characteristics. This machine learning approach enhances MOF development efficiency without the need for synthesis. The atomic graph accurately represents structural features, with graph kernels assessing similarities. A unified kernel, utilizing a weighted RBF kernel, measures MOF similarity and predicts ideal metal and ligand combinations. A support vector machine classification algorithm facilitates metal similarity assessment. This method can yield high specific surface area MOFs. Experiments using data from the CoRE MOF dataset demonstrate accurate predictive model generation for six of the seven well-known graph kernels in the literature. [ABSTRACT FROM AUTHOR]

[Display omitted] Over the last few decades, significant research efforts have been devoted to developing new cleaning systems aimed at preserving cultural heritage. One of the main objectives is to selectively remove aged or undesirable coatings from painted surfaces while preventing the cleaning solvent from permeating and engaging with the pictorial layers. In this work, we propose the use of electrospun polyamide 6,6 nonwovens in conjunction with a green solvent (dimethyl carbonate). By adjusting the electrospinning parameters, we produced three distinct nonwovens with varying average fiber diameters, ranging from 0.4 μm to 2 μm. These samples were characterized and tested for their efficacy in removing dammar varnish from painted surfaces. In particular, the cleaning process was monitored using macroscale PL (photoluminescence) imaging in real-time, while post-application examination of the mats was performed through scanning electron microscopy. The solvent evaporation rate from the different nonwovens was evaluated using gravimetric analysis and Proton Transfer Reaction- Time-of-Flight. It was observed that the application of the nonwovens with small or intermediate pore sizes for the removal of the terpenic varnish resulted in the swollen resin being absorbed into the mats, showcasing a peel-off effect. Thus, this protocol eliminates the need for further potentially detrimental removal procedures involving cotton swabs. The experimental data suggests that the peel-off effect relates to the microporosity of the mats, which enhances the capillary rise of the swollen varnish. Furthermore, the application of these systems to historical paintings underwent preliminary validation using a real painting from the 20th century. [ABSTRACT FROM AUTHOR]

This research aims to determine the aetiology of porosity and subperiosteal new bone formation on the inferior surface of the pars basilaris. A total of 199 non-adult individuals aged 36 weeks gestation to 3.5 years, from a total of 12 archaeological sites throughout the UK, including Iron Age (n=43), Roman (n=12), and post-medieval (n=145) sites, with a preserved pars basilaris. The pars basilaris was divided into six segments, with porosity (micro and macro) and subperiosteal new bone formation recorded on the inferior surface in scorbutic and non-scorbutic individuals. Scurvy was diagnosed using criteria from the palaeopathological literature that was developed using a biological approach. There was no statistically significant difference in microporosity between scorbutic and non-scorbutic individuals in four out of the six segments analysed. There was a significant negative correlation between age and microporosity in non-scorbutic and scorbutic individuals. A significant difference in subperiosteal new bone formation was observed between scorbutic and non-scorbutic individuals. Microporosity on the inferior pars basilaris should not be considered among the suite of lesions included in the macroscopic assessment of scurvy in non-adult skeletal remains (less than 3.5 years). This study highlights the risk of over diagnosing scurvy in past populations. It is difficult to distinguish between physiological (normal) and pathological (abnormal) bone changes in the skeleton of individuals less than one year of age. Future research should focus on the analysis of individuals over 3.5 years of age. [ABSTRACT FROM AUTHOR]

This paper deals with the problems faced during the research on the insulating structures used in the thermal shielding of flight recorders. These structures are characterised by specific properties determined by, among other aspects, their porosity. The complex and coupled heat-exchange phenomena occurring under the operating conditions of the recorders, and in numerous cases combined with mass exchange, require dedicated test methods. The paper characterises the origin of the research problem, presents a methodology for comprehensive testing of the thermal propertiesand uses the example of determining the insulating properties of the Promalight microporous structure ®-1000R. The authors focussed on thermal diffusivity tests performed by means of the oscillatory excitation method. The measurements were conducted on a test stand to determine the effect the type of gas filling had on the porous structure and the pore filling gaspressure effect on the temperature characteristics of apparent thermal diffusivity. The authors also conducted research on the structure's resistance to direct flame exposure. The analysis of the obtained results enable recognition and characterisation of the key phenomena of heat and mass transfer; the numerical results exert a significant influence on their application. [ABSTRACT FROM AUTHOR]

Geochemically driven alterations of fractures in multi‐mineral media can create altered layers (ALs) at the fracture‐matrix interface. Spatial variations in the AL significantly influence mass transfer across the interface, and the hydraulic and mechanical properties of the fractured medium. A real‐rock based microfluidic experiment reported spatial variations in AL thickness despite the initially smooth fracture surface, suggesting potential effects of matrix heterogeneity on AL development. However, the respective contribution of structural and mineralogical characteristics is still poorly understood. Using the microfluidic experimental data and a micro‐continuum reactive transport model, we systematically evaluated how micro‐porosity and initial mineral texture impact AL development and thus the overall reactive transport behaviors. Our simulation results confirmed that the extent of AL spatial variations, mainly controlled by mineralogical texture, influences the evolution of reaction and permeability in different ways. Accounting for spatial heterogeneity in mineral distribution produces "channeling" structures in ALs and lower overall reaction (by up to 35.6%), but larger permeability increase (by up to 9.8%). The characteristic length of the reactive mineral cluster was observed to dominate the internal texture of ALs. Whereas the presence of micro‐porosity can enhance mineral accessibility via improving connectivity for flow and transport, and lead to both higher bulk reaction, that is, thicker ALs, and permeability enhancement. Considerations of surface roughness with characteristic length on the same order of magnitude as mineral texture did not change the overall development of AL, which further highlights the importance of accounting for rock matrix properties in predicting long‐term evolution of fractured media. The resulting spatial variations of ALs and their impacts on bulk properties, however, are expected to be further complicated by the coupling of chemical and mechanical processes, and may trigger matrix disaggregation, erosion and other mechanisms of fractured media alteration. Key Points: Spatial variations in altered layers affect the evolution of bulk reaction and permeability in fractured mediaThe characteristic length of reactive mineral clusters dominates the internal texture of the altered layer and permeability enhancementThe presence of micro‐porosity in the matrix promotes mineral accessibility, reactive transport, and thus thickening of altered layers [ABSTRACT FROM AUTHOR]

Oak-tree-based white charcoals were subjected to high-temperature heat treatment at up to 2400 °C to analyze changes in their surface morphology and internal structure using scanning electron microscopy and transmission electron microscopy. When the treatment temperature was increased, micropores became smaller and disappeared, but macropores and mesopores remained, resulting in an increase in average pore size. At treatment temperatures of 2000 °C or higher, all the pores disappeared and the internal structure changed into a dense graphite-like structure. The X-ray diffraction patterns of charcoals heat-treated at 1800 °C or higher in an argon atmosphere exhibited a sharp peak near 2θ = 26.5°, and Raman spectroscopy showed clear D and 2D bands near 1360 and 2680 cm−1, respectively, indicating that carbon graphite crystals were developing. At 2400 °C for 10 min., the interlayer distances (d002 and d100), Lc and La of the graphite crystallites were 0.34, 0.21, 23.00, and 6.13 nm, respectively. The presence of the D band and the IG/(IG + ID) ratio confirmed that the newly developed structure was turbostratic. The Brunauer–Emmett–Teller (BET) adsorption isotherm of the as-received charcoals exhibited peculiar characteristics in which Types I and IV were mixed. This result is due to low-pressure hysteresis, in which nitrogen is embedded in the crevices of charcoal during adsorption and is hardly desorbed during desorption. This low-pressure hysteresis disappeared as increasing the temperature, the adsorption isotherm of charcoal treated at 2400 °C was Type II, and the specific surface area was 8.45 m2/g, indicating that the charcoal was completely transformed to nonporous graphite. [ABSTRACT FROM AUTHOR]

Oxygen reduction is one of the core steps of non-emissive zero carbon energy conversion. Therefore, enhancement of its sluggish kinetics is extremely important. Very recently researchers focused on oxygen electrocatalysis at porous polymers. Here we applied the non-metalated and pyrolysis free hypercrosslinked polymers with high specific surface area and abundant active sites. Electrode modified with the copolymer prepared from the twisted triphenylbenzene and N containing triphenyl amine exhibits electrocatalytic ORR in alkaline medium. Tafel slope value (0.067 V dec−1) indicates the efficient electrocatalytic activity and fast reaction kinetics. The lack of H2O2 product detected by scanning electrochemical microscopy suggests 4-electron path. The electrocatalytic activity of electrodes modified with hypercrosslinked polymers prepared from single monomers is also seen.

Abstract Al‐Si alloys are widely used in automotive casting components while microporosity has always been a detrimental defect that leads to property degradation. In this study, a coupled three‐dimensional cellular automata (CA) model has been used to predict the hydrogen porosity as functions of cooling rate and initial hydrogen concentration. By quantifying the pore characteristics, it has been found that the average equivalent pore diameter decreases from 40.43 to 23.98 μm and the pore number density increases from 10.3 to 26.6 mm−3 as the cooling rate changes from 2.6 to 19.4°C/s at the initial hydrogen concentration of 0.25 mL/100 g. It is also notable that the pore size increases as the initial hydrogen concentration changes from 0.15 to 0.25 mL/100 g while the pore number remains stable. In addition, the linear regression between secondary dendrite arm spacing and the equivalent pore diameter has been studied for the first time, matching well with experiments. This work exhibits the application of CA model in future process optimization and robust condition design for advanced automotive parts made of Al‐Si alloys.

An original model of microstructural transformations during clay swelling is considered, a thermodynamic and physical-mechanical description of the properties of clays during the process of swelling in vapors and aqueous solutions is given. The model proposed to explain these properties is based on the concept of mutual displacement of clay particles in clay rock aggregates during swelling with the formation of new pores between clay particles forming crystallites and aggregates. The model is based on the mechanism of utilization of the excess surface energy of clay particles during hydration, taking into account the influence of certain environmental parameters, for example, the concentration of the solution, through a change in the mutual orientation of clay particles, mainly due to rotations or shifts relative to each other, with the formation of an area available for further wetting free surface. In the thermodynamic description, such a process will manifest itself in a change in the surface interaction energy on the wetted areas of the particles when moving during mutual shifts and rotations. At the same time, one of the most important parameters of clay rock, microporosity, also changes. In this work, this phenomenon was experimentally studied using the methods of static moisture capacity and Mössbauer (NGR) spectroscopy. The proposed model makes it possible to explain the features of the clay hydration process and to compare the observed experimental data with the theoretical description of the clay swelling process.

The fabrication of membranes for gas separation presents challenges that hinder their deployment as a truly sustainable technology. This review systematically explores the evolution and advancements in materials and manufacturing methods of polymer-based membranes, with a keen emphasis on sustainability and efficiency. The review delineates a broad spectrum of manufacturing techniques, ranging from traditional methods to cutting-edge approaches such as layer-by-layer assembly, and green synthesis, highlighting their implications for environmental sustainability, performance enhancement, scalability, and economic viability. Key findings indicate a significant shift towards greener solvents, bio-based polymers and processes that reduce waste and costs. Critical analysis uncovers a growing focus on understanding the life cycle of membranes and developing strategies for end-of-life such as recycling and the use of biodegradable materials, underscoring the commitment of the community to minimizing environmental footprints. [ABSTRACT FROM AUTHOR]

Chemical sensing of harmful species released either from natural or anthropogenic activities is critical to ensuring human safety and health. Over the last decade, conjugated microporous polymers (CMPs) have been proven to be potential sensor materials with the possibility of realizing sensing devices for practical applications. CMPs found to be unique among other porous materials such as metal–organic frameworks (MOFs) and covalent organic frameworks (COFs) due to their high chemical/thermal stability, high surface area, microporosity, efficient host–guest interactions with the analyte, efficient exciton migration along the π‐conjugated chains, and tailorable structure to target specific analytes. Several CMP‐based optical, electrochemical, colorimetric, and ratiometric sensors with excellent selectivity and sensing performance were reported. This review comprehensively discusses the advances in CMP chemical sensors (powders and thin films) in the detection of nitroaromatic explosives, chemical warfare agents, anions, metal ions, biomolecules, iodine, and volatile organic compounds (VOCs), with simultaneous delineation of design strategy principles guiding the selectivity and sensitivity of CMP. Preceding this, various photophysical mechanisms responsible for chemical sensing are discussed in detail for convenience. Finally, future challenges to be addressed in the field of CMP chemical sensors are discussed. [ABSTRACT FROM AUTHOR]

Heavy metal ions have a serious effect on humans and the ecosystem. Molecular sieves have attracted significant attention in heavy metal ion adsorption with distinct microporosity and uniform pore size. In this paper, we successfully synthesized nano-sized NaA molecular sieves in the presence of an organic templating agent while aluminum isopropoxide and silica sol were used as the aluminum and silica sources. To synthesize molecular sieves of the ideal size, the anionic cation concentration and templating agent were adjusted. The findings of Cu(II) and Pb(II) adsorption on NaA molecular sieves showed that under the ideal conditions of adsorption time at 90 minutes, pH = 5, adsorption temperature at 25 °C, and starting adsorbent concentration at 100 mg g−1, the optimal adsorbing capacity could reach 230 mg g−1 and 600 mg g−1, respectively. Isotherm, kinetic, thermodynamic and reusability studies of heavy metal ion adsorption on NaA molecular sieves were carried out to investigate the adsorption kinetics. This work provides a new avenue to regulate the particle sizes of molecular sieves to enhance the adsorption capacity of heavy metal ions. [ABSTRACT FROM AUTHOR]

• A simple and efficient one-pot synthesis route was successfully conducted. • Petroleum coke-based microporous carbon exhibits high CO 2 uptake (4.25 mmol/g at 25°C and 1 bar) and specific capacitance (233.25 F/g at 0.5A/g). • Ultra-micropores and basic N species are crucial factors for the enhanced CO 2 uptake and CO 2 /N 2 selectivity respectively. • Waste resource utilization and global CO 2 emission reduction can be realized simultaneously. Waste resource utilization of petroleum coke is crucial for achieving global carbon emission reduction. Herein, a series of N-doped microporous carbons were fabricated from petroleum coke using a one-pot synthesis method. The as-prepared samples had a large specific surface area (up to 2512 m2/g), a moderate-high N content (up to 4.82 at.%), and high population (55%) of ultra-micropores (<0.7 nm). Regulating the N content and ultra-microporosity led to efficient CO 2 adsorption and separation. At ambient pressure, the optimal N-doped petroleum coke-based microporous carbon exhibited the highest CO 2 uptake of 4.25 mmol/g at 25°C and 6.57 mmol/g at 0°C. These values are comparable or even better than those of numerous previously reported adsorbents prepared by multistep synthesis, primarily due to the existence of ultra-micropores. The sample exhibited excellent CO 2 /N 2 selectivity at 25°C owing to the abundant basic pyridinic and pyrrolic N species; and showed superior CO 2 adsorption-desorption cycling performance, which was maintained at 97% after 10 cycles at 25°C. Moreover, petroleum coke-based microporous carbon, with a considerably high specific surface area and hierarchical pore structure, exhibited excellent electrochemical performance over the N-doped sample, maintaining a favorable specific capacitance of 233.25 F/g at 0.5 A/g in 6 mol/L KOH aqueous electrolyte. This study provides insight into the influence of N-doping on the porous properties of petroleum coke-based carbon. Furthermore, the as-prepared carbons were found to be promising adsorbents for CO 2 adsorption, CO 2 /N 2 separation and electrochemical application. [Display omitted] [ABSTRACT FROM AUTHOR]

Developing high‐performance carbonaceous anode materials for sodium‐ion batteries (SIBs) is still a grand quest for a more sustainable future of energy storage. Introducing sulfur within a carbon framework is one of the most promising attempts toward the development of highly efficient anode materials. Herein, a microporous sulfur‐rich carbon anode obtained from a liquid sulfur‐containing oligomer is introduced. The sodium storage mechanism shifts from surface‐controlled to diffusion‐controlled at higher synthesis temperatures. The different storage mechanisms and electrode performances are found to be independent of the bare electrode material's interplanar spacing. Therefore, these differences are attributed to an increased microporosity and a thiophene‐rich chemical environment. The combination of these properties enables extending the plateau region to higher potential and achieving reversible overpotential sodium storage. Moreover, in‐operando small‐angle X‐ray scattering (SAXS) reveals reversible electron density variations within the pore structure, in good agreement with the pore‐filling sodium storage mechanism occurring in hard carbons (HCs). Eventually, the depicted framework will enable the design of high‐performance anode materials for sodium‐ion batteries with competitive energy density. [ABSTRACT FROM AUTHOR]