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Purpose: To evaluate the reliability of various reference areas for digital alignment between 3D resting and smiling facial models. Materials and Methods: 3D posed and natural smiling faces of 33 adults were registered to the respective neutral faces, using six matching strategies with different reference matching surfaces: nose (N), nose + central forehead (NFc), nose + whole forehead (NFw), nose + chin (NC), nose + central forehead + chin (NFcC), and nose + whole forehead + chin (NFwC). The positional discrepancies of the registered images were measured at the left and right pupil centers. Results: Two-way ANOVA and post hoc multiple pairwise t test with Bonferroni correction (α = .05) were used to evaluate the measurements. As a result, the use of larger reference areas increases the trueness of image-matching, whereas there was no statistically significant difference between the matching strategies within the same smiling type. Meanwhile, the image registration of posed smiles resulted in fewer positional disparities than the natural smiles with significant differences observed for the registration using the NC and NFcC surface-based matching areas at the right pupil (P = .030 and .026, respectively). Conclusions: The findings of this study suggest that the reference surface areas and smiling types have some impact on the accuracy of 3D smiling facial image alignments. Large and evenly distributed matching surfaces are recommended for posed smiles, whereas caution should be taken when using the chin area as a reference surface for matching natural smile facial images. [ABSTRACT FROM AUTHOR]

Exposure to ambient air contaminates the surface of graphene sheets. Contamination may arise from different sources, and its nature alters the frictional behavior of the material. These changes in friction enable the observation of the early stages of contaminants' adsorption in graphene. Using a friction force microscope, we show that molecular adsorption initiates at the edges and mechanical defects in the monolayer. Once the monolayer is covered, the contaminants spread over the additional graphene layers. With this method, we estimate the contamination kinetics. In monolayer graphene, the surface area covered with adsorbed molecules increases with time of air exposure at a rate of 10−14 m2/s, while in bilayer graphene, it is one order of magnitude smaller. Finally, as the contaminants cover the additional graphene layers, friction no longer has a difference concerning the number of graphene layers. [ABSTRACT FROM AUTHOR]

Coagulational growth in an aerosol is a multistep process; first particles collide, and then they coalesce with one another. Coalescence kinetics have been investigated in numerous prior studies, largely through atomistic simulations of nanoclusters (102–104 atoms). However, with a few exceptions, they have either assumed the process is completely isothermal or is a constant energy process. During coalescence, there is the formation of new bonds, decreasing potential energy, and correspondingly increasing internal kinetic (thermal) energy. Internal kinetic energy evolution is dependent not only on coalescence kinetics but also on heat transfer to the surrounding gas. Here, we develop and test a model of internal kinetic energy evolution in collisionally formed nanoclusters in the presence of a background gas. We find that internal kinetic energy dynamics hinge upon a power law relationship describing latent-to-sensible heat release as well as a modified thermal accommodation coefficient. The model is tested against atomistic models of 1.5–3.0 nm embedded-atom gold nanocluster sintering in argon and helium environments. The model results are in excellent agreement with the simulation results for all tested conditions. Results show that nanocluster effective temperatures can increase by hundreds of Kelvin due to coalescence, but that the rise and re-equilibration of the internal kinetic energy is strongly dependent on the background gas environment. Interestingly, internal kinetic energy change kinetics are also found to be distinct from surface area change kinetics, suggesting that modeling coalescence heat release solely due to surface area change is inaccurate. [ABSTRACT FROM AUTHOR]

The power-law fluid flow in tree-like self-similar branching networks is prevalent throughout the natural world and also finds numerous applications in technology such as oil recovery and microfluidic devices. We investigate analysis of optimal power-law fluid flow conditions and the optimal structures within tree-like branching networks, focusing on maximizing flow conductance under the constraint of the network tube's volume and the surface area. The study considered fully developed laminar power-law fluid flow regimes without considering any losses in the network system. A key observation was the sensitivity of the dimensionless effective flow conductance to the network's geometrical parameters. We found that the maximum flow conductance occurs when a dimensionless radius ratio β ∗ satisfies the equation β ∗ = N − 1 / 3 and β ∗ = N − (n + 1) / (3 n + 2) under constrained tube-volume and surface-area, respectively. Here, N represents the bifurcation number of branches splitting at each junction, and n is the fluid power-law index. We further find that this optimal condition occurs when pressure drops are equipartition across each branching level. We validated our results with various experimental results and theories under limiting conditions. Further, Hess–Murray's law is justified and extended for the shear-thinning and shear-thickening fluid flows for an arbitrary number of branches N. Further, in this study, we also derive the relationships between the geometrical and flow characteristics of the parent and daughter tubes as well as the generalized scaling laws at the optimal conditions for the other essential parameters such as tube-wall stresses, length ratios, mean velocities, tube-volume, and surface-area of the tube distributing within the networks. We find that the fluid power-law index n does not influence the constrained tube-volume scaling at the optimal conditions; however, the scaling laws vary with n under the constrained tube's surface area. These findings offer valuable design principles for developing efficient transport and flow systems. [ABSTRACT FROM AUTHOR]

Pyrogenic silica is a form of amorphous silica with a high surface area and a heterogeneous distribution of silanol hydroxyl terminations and defects. In this work, the interesting and unusual form of the hydroxyl-stretch 2D-IR spectrum of pyrogenic silica is presented and explored in the deuterated (deuteroxyl) form. Transition dipole couplings between hydrogen-bonded and non-hydrogen-bonded silanol groups give a distinct cross-peak in the 2D-IR spectrum, displaying interstate coherence oscillations during the 2D-IR experimental waiting time. The strong asymmetry about the diagonal is proposed to be the result of both the relatively small transition dipole coupling strength and the extreme differences in the width of the hydrogen-bonded and non-hydrogen-bonded silanol bands. The resulting interference of negative and positive cross-peaks has minimal intensity in the below-diagonal ω3 < ω1 region of the spectrum. An additional strong positive cross-peak is observed at a position in the 2D-IR spectrum inconsistent with transition dipole coupling. An assignment as a fifth order effect is proposed. [ABSTRACT FROM AUTHOR]

We present results of resonant ultrasound spectroscopy (RUS) measurements applied to granular high explosive materials at different bulk pressing densities and degree of thermal conditioning. The material chosen in this study is a ubiquitously used explosive material known as pentaerythritol tetranitrate (PETN), which is used commercially in civil and defense applications both as a binderized plastic bonded explosive material and an unbinderized neat material. However, changes in granular PETN bulk elastic properties due to thermal conditioning, which could have implications for better understanding environmental aging-related effects, have not been well studied even though it is believed that elasticity may play an important role in explosive material initiation mechanisms. Furthermore, monitoring elastic property changes in granular explosive pressings has not yet been demonstrated using RUS, which is an appealing non-destructive characterization tool that requires only dry point contact with the explosive material. To this end, we report the first study using RUS to quantify the elastic properties of binderized and neat PETN pressings as well as to quantify changes in elastic properties as a function of both thermal conditioning and bulk pressing density. Elastic stiffness coefficients, sometimes more commonly referred to as elastic constants, calculated from the RUS measurements on the different PETN-based materials show a significant increase for the post-conditioned samples compared to the pre-conditioned samples. This trend of increasing elastic properties with thermal conditioning was consistent for different density pressings, different thermal exposure conditions, and even different neat PETN pressings of differing average crystal sizes and/or specific surface areas. [ABSTRACT FROM AUTHOR]

In this paper, polarization-stable and spectrally single-mode operation of oxide-confined multi-junction vertical-cavity surface-emitting lasers (VCSELs) are achieved by using a non-circular integrated anti-phase transverse mode filter. A record-high single-mode output power is obtained by radially reducing effective mirror reflectivity at the surface areas where the higher order modes are expected to lase, leading to an increase in the threshold gain for these transverse modes, all the while minimal losses are introduced to the fundamental mode. The polarization control of such devices is achieved by using a non-circular mode filter in order to perturb the cylindrical symmetry of the cavity. An elliptically etched surface relief is shown to be effective in realizing a single-mode single-polarization device over a wide range of operating bias currents and temperatures. The continuous-wave light–current–voltage characteristics of 8-junction 940 nm VCSELs show single-mode output power >13 mW at room temperature, spectrally measured with a side-mode suppression ratio of >30 dB. This single-mode performance can be achieved depending on the ratio between the relief opening and the oxide aperture size. Additionally, the single-polarization behavior of such devices (with an extinction ratio of >15 dB) is shown to be dependent on the orientation of the elliptical mode filter, where the light is mainly polarized along the minor axis of the elliptical feature. Overall, combined with a multi-junction active region, the elliptical model filter is able to achieve highly efficient single-mode linearly polarized VCSELs. [ABSTRACT FROM AUTHOR]

We extend an existing thermophysical activity model of comet 67P/Churyumov–Gerasimenko to include pressure build-up inside the pebbles making up the nucleus. We test various quantities of H |$_{2}$| O and CO |$_{2}$|⁠ , in order to simulate the material inside and outside of proposed water enriched bodies (WEBs). We find that WEBs can reproduce the peak water flux observed by Rosetta , but that the addition of a time-resolved heat-flow reduces the water fluxes away from perihelion as compared to the previously assumed equilibrium model. Our modelled WEBs eject dust continuously but with a rate that is much higher than the observed erosion and mass-loss, thus requiring an active area smaller than the total comet surface area or very large quantities of dust fallback. When simulating the CO |$_{2}$| -rich non-WEB material, we only find the ejection of large chunks under specific conditions (e.g. low diffusivities between the pebbles or intense insolation at southern summer), while we also find CO |$_{2}$| outgassing rates that are much greater than observed. This is a general problem in models where CO |$_{2}$| drives erosion, alongside difficulties in simultaneously ejecting chunks from deep while eroding the surface layer. We therefore conclude that ejection of chunks by CO |$_{2}$| must be a localized phenomenon, occurring separately in space or time from surface erosion and water emission. Simulating the global production rates of gas, dust, and chunks from a comet thus remains challenging, while the activity mechanism is shown to be very sensitive to the material structure (i.e. porosity and diffusivity) at various scales. [ABSTRACT FROM AUTHOR]

We synthesized a WNT5A β-hairpin peptide responsible for the protein's binding to its receptor, Frizzled. Full affinity to Frizzled requires all three disulfides but not an invariant tryptophan that significantly contributes to the buried surface area. Our work opens the avenue to target the Wnt–Fzd interface using synthetic peptides. [ABSTRACT FROM AUTHOR]

Polyoxometalate-based metal–organic frameworks (POMOFs) are highly effective heterogeneous catalysts that combine the catalytic activity of polyoxometalates (POMs) with the high surface area, tunable porosity, and structural diversity of MOFs. Nevertheless, there is still a lack of a general method to integrate POMs with various transition metal-based building units into POMOFs under mild conditions. In this work, we employed imine bonds to link amino-functionalized Anderson-type POMs with aldehyde-terminated divalent metal clusters, resulting in a series of isostructural POMOFs, M(II)-POMOFs (M = Zn, Co, Mg, or Mn). Furthermore, we used post-synthetic metal exchange and oxidation to transform Zn-POMOF into Fe(III)-POMOF with strong Lewis acidic Fe3+ sites. Notably, both the synthesis and post-synthetic modifications were performed under mild conditions (room temperature, acid-free), preventing the decomposition of the POMs. Compared to M(II)-POMOFs or MOFs without POMs, the combination of Lewis acidic Fe3+ and POMs enhanced its catalytic activity for CO2 cycloaddition with epoxides, enabling efficient synthesis of cyclic carbonates. This versatile synthetic method could broaden the scope of POMOFs, extending their applications in catalysis and beyond. [ABSTRACT FROM AUTHOR]

Oligomerization presents a wide range of opportunities for transforming light olefins into liquid fuels. This study centers on a novel catalyst system – phosphotungstic acid (PW) loaded onto MCM-41 prepared via impregnation, aiming to tackle these challenges. The ordered mesoporous structure, high surface area, and facile recovery of MCM-41 make it an ideal support for PW. Under the mild reaction conditions of 70 °C, 1 MPa, and 5 h, the 20% PW/MCM-41 catalyst exhibited remarkable catalytic performance, achieving an isopentene conversion rate of 77.8%, a selectivity of 93.5% towards the C10 dimer product, and a yield of 72.7%. Encouragingly, the catalyst could be reused without special treatment, maintaining a selectivity above 93% for the C10 dimer product over five cycles, showcasing outstanding stability and regeneration capability. This research not only provides robust insights into catalyst design for isopentene dimerization but also paves the way for sustainable advancements in industrial catalysis. [ABSTRACT FROM AUTHOR]

Ordered porous materials can offer more accessible catalytic sites and large buffer space for discharge products, thus improving cell performance. In this paper, a simple down-top solution-precipitation method followed by pyrolysis was proposed to disperse active nickel–cobalt-NC sites in ZIF-derived porous carbon nanocages. It was found that these metal nanoparticles were confined in the N-enriched carbon nanocage with a total metal loading of about 8.74 at%. As expected, this porous structure not only enhances electron conductivity, but also provides a sufficient surface area to facilitate the triphasic cell reaction and create more space for the storage of discharge products. Experimental findings confirm that this interesting nanostructure manifests an increase in capacity (6682.6 mA h g−1), coulombic efficiency (∼100%) and cycling performance (∼80 cycles) over the control group for quasi-solid-state cells. Benefitting from the addition of Ni to modify the porous structure, the O2/ion diffusion pathway and accessible active sites are enriched, yielding faster redox kinetics and lower overpotential (high reversibility). Thus, our work demonstrates that this type of porous bimetallic nanocage is promising for fabricating efficient biomass quasi-solid-state Li–O2 batteries. [ABSTRACT FROM AUTHOR]

The photocatalytic performance of chitosan-derived catalytic films deteriorates due to surface area loss during catalyst immobilization. It limits the practical efficacy of these films, despite being a greener and more reusable alternative to powdered catalysts. Herein, we have restored and enhanced the photocatalytic efficiency of chitosan films from 67% to 95% by starch impregnation. The combinatorial impact of the enhanced adsorption due to the unique surface structure of the starch–chitosan surface and cooperative charge separation efficiency of the photocatalyst balance the effect of surface area loss and photocatalytic performance is restored. [ABSTRACT FROM AUTHOR]

Herein, a Bi2Fe4O9@Bi25FeO40 heterostructure with a high specific surface area of 30.07 m² g-1 and abundant heterogeneous interfaces was successfully fabricated and applied to supercapacitors for the first time. The Bi2Fe4O9@Bi25FeO40 electrode exhibits a high specific capacity (550.8 F g-1 at 1.0 A g-1) and good cycling stability (75% capacitance retention and 92.3% coulombic efficiency after 3000 cycles at 5.0 A g-1), significantly outperforming the pure Bi2Fe4O9 or Bi25FeO40 electrode. This work proposes an effective interfacial engineering strategy to enhance supercapacitor performance. [ABSTRACT FROM AUTHOR]

The development of nanofiber sponge materials with three-dimensional structures, high porosities, and large specific surface areas is crucial for the rapid separation of water-in-oil emulsions. In this study, we fabricated Janus mullite nanofiber (MNF) sponges with efficient oil–water separation performance using a novel combination of electrostatic-assisted solution blow spinning (E -SBS) and in situ growth. MNF sponges weighing 0.074 g were subjected to 100 compression cycles, with the stress reducing to 85.6 % of its initial value after impregnation with ZIF-8 nanoparticles and OTS. Consequently, the MNF sponges changed from hydrophilic to hydrophobic, and after 20 separation experiments, they still maintained high separation fluxes for oil–water mixtures and emulsions, achieving 7959 and 1803 L m−2 h−1, respectively. Moreover, the preparation process of the MNF sponges is environmentally friendly, causing no environmental pollution. Therefore, Janus MNF sponges show great potential for applications in oil–water separation. [Display omitted] • Janus MNF sponges exhibit efficient oil–water separation. • Green preparation process offers an eco-friendly solution. • Maintained high separation fluxes after 20 experiments. • Hydrophilic to hydrophobic transition enhances performance. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of CO 2 into valuable fuels is considered a promising approach for the development of sustainable and renewable energy sources. In this study, we utilized Mo-MOF as a precursor to obtain MoO 3 by pyrolytic derivatization and treated it to obtain MOF-MoO 3-x containing oxygen vacancies as a catalyst for the photocatalytic reduction of CO 2 to CO. MOF derivatization altered the morphology of the MoO 3 , which made the formation of oxygen vacancies easier and facilitated the separation of electron-hole pairs. Meanwhile, the increased specific surface area and the appearance of surface oxygen vacancies enhanced the CO 2 adsorption and activation capabilities of MOF-MoO 3-x. As a result, MOF-MoO 3-x demonstrated a significant enhances in the photoreduction activity of CO 2. Its CO yield was 29.1 μmolg−1h−1, which was 3.7 times higher than that of MOF-MoO 3 and 2.4 times higher than that of H-MoO 3-x. This innovative strategy may provide a new avenue for improving the comprehensive performance of photocatalysts and developing renewable energy sources. MOF-MoO 3-x photocatalytic material derived from Mo-MOF precursor and prepared by ascorbic acid reduction. Compared to the H-MoO 3-x obtained by hydrothermal method, the MOF structure promoted the formation of oxygen defects, the yield of CO reduction by MOF-MoO 3-x had been significantly improved. [Display omitted] [ABSTRACT FROM AUTHOR]

Appropriate element doping is an important means to improve gas response. Pure and Zn-doped CoTiO3 nanoparticles were fabricated by a simple sol–gel method and their gas response to ethanol and acetone was studied. Compared with pure CoTiO3 nanoparticles, particle dispersion, specific surface area, oxygen vacancy defects, and gas-sensitive properties of Zn-doped CoTiO3 nanoparticles are optimized and improved. With the increase of Zn doping concentration, the aggregates composed of irregular nanoparticles disperse loosely and the oxygen vacancy defects on the CoTiO3 nanoparticles' surface accordingly increase. The optimum operating temperature of Zn-doped CoTiO3 nanoparticles is slightly reduced from 286 to 260 °C. CoTiO3 nanoparticles with Zn doping concentration of 0.05 especially show excellent gas-sensing properties. The sensitivities of Co0.95Zn0.05TiO3 nanoparticles to 50 ppm ethanol and acetone are as high as 125.8 and 143.4, increased to 1.98 and 1.74 times higher than those of pure CoTiO3 nanoparticles. The linear fitting of logarithmic relationship between sensitivity and concentration shows that Zn-doped CoTiO3 can accurately detect low concentration (< 100 ppm) of ethanol and acetone. The improvement of gas response of Zn-doped CoTiO3 nanoparticles is proposed to attribute to the synergistic effect of the agglomeration state of irregular particles and abundant oxygen vacancies on the surface due to Zn doping. [ABSTRACT FROM AUTHOR]

Electrospinning technology, capable of creating nanofiber-based materials with large specific surface areas and exceptional breathability, has become an important tool in the biomedical field. Silk, as a well-known natural biopolymer, features good biocompatibility, customizable biodegradability, and superior mechanical properties. The conversion of silk into nanofibers via electrospinning allows for the fine-tuning of its properties, thereby enhancing its suitability for a variety of biomedical applications. Electrospun silk not only inherits the natural advantages of silk but also acquires optimized characteristics such as increased surface area, high porosity, and good air permeability. This review article begins by summarizing the latest advances in the rational design and controlled fabrication of electrospun silk. Then, the biomedical applications of electrospun silk in three main areas: health monitoring, regenerative medicine, and personal protection, are reviewed. Lastly, the existing challenges and future perspectives of electrospun silk are discussed. This review aims to highlight the cutting-edge role of electrospun silk in biomedical applications, potentially revolutionizing traditional healthcare into a personalized model. Highlights: • Rational design, controlled fabrication, and advantages of electrospun silk are discussed. • Biomedical applications, including health monitoring, regenerative medicine, and personal protection are systematically summarized. • Electrospun silk paves a compelling road to biomedical applications for personalized healthcare. [ABSTRACT FROM AUTHOR]

ABSTRACT Experiments and field monitoring have revealed that in block caving, fractures over the cave crown tend to form in narrow curved bands that are parallel or subparallel to the cave back surface. These fractures delineate curved shells of orebody between the bands and the cave back. The effectiveness of block caving hinges on the subsequent fracturing and fragmentation of these orebody shells. This study adopts a dual approach, combining thin spherical shell theory and full 3D numerical simulations along with principles of linear elastic fracture mechanics, to investigate the fracturing behaviour of these shells. Analytical analysis indicates that under axisymmetric loading, latitudinal tensile fractures predominantly initiate across the most part of the shell, occurring on both the upper and lower surfaces, except at a localised area. Additionally, longitudinal tensile fractures may initiate at the central area of the upper surface, while shear fractures tend to occur around the edge of the shell. Consequently, the shells become susceptible to fracturing, leading to the collapse or cave‐in of the orebody. Numerical simulations agree with these findings, illustrating that fracturing points within the shell region are longitudinally dispersed throughout the entire shell. Most of these fracturing points satisfy the criteria for tensile fracturing, particularly within the middle portion of the shell, aligning with the analytical results. Furthermore, simulations considering nonaxisymmetric loading patterns demonstrate that regions surrounding the caving cavity, aligned with the minimum principal in situ stress, exhibit heightened susceptibility to fracture initiation. This insight holds potential significance for optimising the design of the caving process. [ABSTRACT FROM AUTHOR]

A simple two step synthetic method for di‐doped crystalline mesoporous tin dioxide powder containing antimony and fluoride at ambient pressure and temperature has been developed. This approach produced materials with high surface areas and improved electrical and optoelectrical conductance. The two dopant elements; antimony and fluoride were introduced to tin dioxide by two approaches. Both approaches produced mesoporous tin dioxide with antimony and fluoride that are integrated in the framework. The structures of these materials are analyzed by powder X‐ray diffraction, N2 sorption analysis, transmission electron microscopy, energy dispersive X‐ray spectroscopy and X‐ray photoelectron spectroscopy. The conductance of the materials improved by factor of 13–34 compared to undoped mesoporous tin dioxide. The effect of the di‐doped elements on structure, conductance and optoelectronic properties of these materials are discussed in this paper. [ABSTRACT FROM AUTHOR]

Cobalt‐free LiNi0.5Mn1.5O4 (LNMO) is a promising cathode material for high‐energy and power‐density lithium‐ion batteries (LIBs). However, its commercial adoption is hindered by rapid capacity degradation due to the unstable LNMO/electrolyte interface caused by LNMO's high operating voltage. Structural degradation from Jahn–Teller distortion and metal‐ion dissolution also contributes to poor cycling stability. Additionally, producing industrial‐grade LNMO with high tap density, low surface area and reduced metal‐ion dissolution is challenging. This study addresses these challenges through a rational material design approach, synthesizing LNMO with large spherical secondary particles (>14.0 µm) and high tap density (>2.0 g cm−3). The primary particles (1.5–6.0 µm) exhibit a truncated‐octahedral shaped morphology that predominantly exposes (111) surface facets, with fewer (100) surfaces, stabilizing the LNMO/electrolyte interface, reducing metal dissolution, and enhancing lithium‐ion kinetics. Silicon infusion into grain boundaries further improves structural integrity by forming a silicon‐rich phase. The tailored LNMO demonstrates exceptional rate capability, cycling stability, and improved interfacial kinetics, significantly advancing the potential for cobalt‐free LNMO in high‐voltage LIBs. This work highlights the importance of tailored cathode material design for achieving the performance and stability required for emerging high‐voltage LIBs applications. [ABSTRACT FROM AUTHOR]

Mesoporous catalysts with a high specific surface area, accessible pore structures, and appropriate band edges are desirable for optimal charge transfer across the interfaces, suppress electron‐hole recombination, and promote redox reactions at the active sites. The present study demonstrates the rational design of mesoporous ZnFe2O4@g‐C3N4 magnetic nanocomposites (MNCs) with different pore sizes and pore volumes following a combination of facile thermal itching and thermal impregnation methods. The MNCs preserve the structural, morphological, and physical attributes of their counterparts while ensuring their effectiveness and superior catalytic capabilities. The morphological analysis confirms the successful grafting and confinement of ZnFe2O4 nanoparticles with the polymeric g‐C3N4 nanosheets to form heterojunctions with numerous interfaces. The MNCs possess uniformly distributed small mesopores (pore size <4 nm), ample active sites, and a high specific surface area of 62.50 m2/g. The mesoporous ZnFe2O4@g‐C3N4 notably improve hydrogen evolution rate and methylene blue dye degradation. The optimal loading weight of ZnFe2O4 is 20 %, in which the MNCs display the highest hydrogen evolution rate of 1752 μmol g−1 h−1 and photo‐Fenton dye degradation rate constants of 0.147 min−1, upon solar‐light illumination. Furthermore, the photocatalysts demonstrate recyclability over five consecutive cycles, confirming their stability, while easy separation using a simple magnet underscores practical utility. [ABSTRACT FROM AUTHOR]

Food safety is an important issue related to the life and health of all people, and food packaging can effectually protect food from surface damage, mildew, rot, etc., while ensuring food quality to extend the shelf life, effectively preventing food safety problems. Metal–organic frameworks (MOFs) are functional materials with special physical and chemical properties, such as a high specific surface area, high porosity and adjustable structure, which can be designed and adjusted according to the characteristics of different food packaging materials, so they have significant application prospects in food packaging. This review systematically introduced the types and properties of MOFs materials, summarized the methods to synthesize MOFs, and discussed the application progress of MOFs in food packaging by evaluating the safety of MOFs. Further, the potential uses of MOFs in food packaging applications were explored. This review may provide systematic insight into the use of MOFs for food packaging and explore new ideas. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA) granules are frequently used in orthopedics and maxillofacial surgeries to fill bone defects and stimulate the regeneration process. Optimal HA granules should have high biocompatibility, high microporosity and/or mesoporosity, and high specific surface area (SSA), which are essential for their bioabsorbability, high bioactivity (ability to form apatite layer on their surfaces) and good osseointegration with the host tissue. Commercially available HA granules that are sintered at high temperatures (≥ 900 °C) are biocompatible but show low porosity and SSA (2–5 m2/g), reduced bioactivity, poor solubility and thereby, low bioabsorbability. HA granules of high microporosity and SSA can be produced by applying low sintering temperatures (below 900 °C). Nevertheless, although HA sintered at low temperatures shows significantly higher SSA (10–60 m2/g) and improved bioabsorbability, it also exhibits high ion reactivity and cytotoxicity under in vitro conditions. The latter is due to the presence of reaction by-products. Thus, the aim of this study was to fabricate novel biomaterials in the form of granules, composed of hydroxyapatite nanopowder sintered at a high temperature (1100 °C) and a biopolymer matrix: chitosan/agarose or chitosan/β-1,3-glucan (curdlan). It was hypothesized that appropriately selected ingredients would ensure high biocompatibility and microstructural properties comparable to HA sintered at low temperatures. Synthesized granules were subjected to the evaluation of their biological, microstructural, physicochemical, and mechanical properties. The obtained results showed that the developed nanocomposite granules were characterized by a lack of cytotoxicity towards both mouse preosteoblasts and normal human fetal osteoblasts, and supported cell adhesion to their surface. Moreover, produced biomaterials had the ability to induce precipitation of apatite crystals after immersion in simulated body fluid, which, combined with high biocompatibility, should ensure good osseointegration after implantation. Additionally, nanocomposite granules possessed microstructural parameters similar to HA sintered at a low temperature (porosity approx. 50%, SSA approx. 30 m²/g), Young's modulus (5–8 GPa) comparable to cancellous bone, and high fluid absorption capacity. Moreover, the nanocomposites were prone to biodegradation under the influence of enzymatic solution and in an acidic environment. Additionally, it was noted that the hydroxyapatite nanoparticles remaining after the physicochemical dissolution of the biomaterial were easily phagocytosed by mouse macrophages, mouse preosteoblasts, and normal human fetal osteoblasts (in vitro studies). The obtained materials show great potential as bone tissue implantation biomaterials with improved bioresorbability. The obtained materials show great potential as bone tissue implantation biomaterials with improved bioresorbability. [ABSTRACT FROM AUTHOR]

This review examines the advances and applications of metal–organic frameworks (MOFs) in the field of the extraction of uranium from various sources, focusing on their potential to address critical issues in nuclear fuel cycles. MOFs, characterized by their high surface area, tunable porosity, and chemical versatility, offer a promising alternative to traditional extraction methods. The review paper provides a comprehensive analysis of the synthesis strategies, functionalization techniques, and adsorption mechanisms of MOFs tailored for uranium capture. Furthermore, the review discusses the challenges and future directions in the field, emphasizing the need for scalable production, real-world application testing, and environmental impact assessment. This review aims to highlight the potential of MOFs to improve the sustainability and efficiency of uranium extraction processes. [ABSTRACT FROM AUTHOR]

This study reports the characteristics of a piezoelectric nanogenerator (PENG) consisting of a mixture of polydimethylsiloxane (PDMS) and zinc tin oxide (ZTO) particles (ZTO@PDMS) with different shapes and phases. The output performance of PENGs with crystalline Zinc hydroxystannate(ZHS), amorphous ZTO, and crystalline ZTO of different phases was investigated based on annealing temperature. The fabricated PENGs with amorphous ZTO (a-ZTO) cubes showed a maximum output voltage of ∼4.3V and a current of ∼470 nA with a power of 3.14 μW, which is 249 % higher than that of the crystalline ZTO (c-ZTO) cube-based one. The amorphous ZTO (a-ZTO) nanosphere showed the highest output performance. The surface area of the piezoelectric material affected the residual polarization, which led to different piezoelectric properties. Therefore, we investigated the output performance of PENGs with various shapes while maintaining the same volumes of ZTO cubes and spheres. The molar ratio of the materials was varied during synthesis, revealing that the ZTO cubes have a higher output performance. The polarization-electric loops (P-E loops) showed a high remnant polarization (Pr∼25.89μC/cm2) in ZTO@PDMS films with larger 1103 nm cubes. These values were 170.5 %, 143.7 %, and 113.2 % larger than those observed in ZTO@PDMS films with cubes of size 826 nm, 978 nm, and 1047 nm, respectively. The ZTO nanocubes have a significant advantage in the fabrication of high output performance based on PENGs. [ABSTRACT FROM AUTHOR]

The enhancement in the capacitance of a supercapacitor has been successfully achieved by synthesizing Bi 2 WO 6 (BW), TiS 2 (T), and Bi 2 WO 6 /TiS 2 (BW/T) composites utilizing the hydrothermal process. The possible growth mechanism has also been presented. The morphological and structural characteristics of the cultivated samples were observed using FT-IR, XRD, SEM, EDS, and UV–vis spectroscopy techniques. TiS 2 nano platelets uniformly dispersed across the hierarchically opened surface of Bi 2 WO 6 in the synthesized hierarchical composite. This leads to an increase in surface porosity and surface area, which in turn enhances the transport of electrons and ions on the composite BW/T surface. The optimal electrode BW/T@40 % composite electrode shown a substantial enhancement in particular capacitance (1153.3 F/g) compared to the separate BW (523.7 F/g) and T (453.3 F/g) electrodes due to its rapid ion transfer, many active sites on its large surface area, and strong synergistic impact. Furthermore, the BW/T@40 % combination demonstrated exceptional stability, with over 92 % of its capacitance maintained after 4500th cycles and b value (0.71) proved the supercapacitor behavior. Therefore, BW/T@40 % binary metal oxide and sulfide composites exhibit improved specific capacitance and greatly prolonged life-cycle, confirming its potential use in high-performance energy storage devices. [ABSTRACT FROM AUTHOR]

The influence of polar, water-miscible organic solvents (POS) on protein structure, stability, and functional activity is a subject of significant interest and complexity. This study examines the effects of acetonitrile (ACN), a semipolar, aprotic solvent, on the solvation properties of blocked Ace-Gly-X-Gly-Nme tripeptides (where Ace and Nme stands for acetyl and N-methyl amide groups respectively and X is any amino acid) through extensive molecular dynamics simulations. Individual simulations were conducted for each peptide, encompassing five different ACN concentrations within the range of χACN = 0.1–0.9. The preferential solvation parameter (Γ) calculated using the Kirkwood-Buff integral method was used for the assessment of peptide interactions with water/ACN. Additionally, weighted Voronoi tessellation was applied to obtain a three-way data set containing four time-averaged contact surface area types between peptide atoms and water/ACN atoms. A mathematical technique known as N-way Partial Least Squares (NPLS) was utilized to anticipate the preferential interactions between peptides and water/ACN from the contact surface areas. Furthermore, the temperature dependency of peptide-solvent interactions was investigated using a subset of 10 amino acids representing a range of hydrophobicities. MD simulations were conducted at five temperatures, spanning from 283 to 343 K, with subsequent analysis of data focusing on both preferential solvation and peptide-solvent contact surface areas. The results demonstrate the efficacy of utilizing contact surface areas between the peptide and solvent constituents for successfully predicting preferential interactions in water/ACN mixtures across various ACN concentrations and temperatures. [ABSTRACT FROM AUTHOR]

In contrast to natural enzymes, nanozymes show promising advantages of low cost and high stability for analytical applications. The simple mix of L -phenylalanine (F) and Cu2+ produces two-dimensional nanosheets of a coordination polymer with a high surface area ratio and rich exposed active sites as a novel catalyst. As the mimetic of natural laccase, this nanozyme (F–Cu) can catalyze the oxidative coupling reaction of 2,4-dichlorophenol (2,4-DP) and 4-aminoantipyrine (4-AP) to produce a distinct red product, thus establishing an intuitive and simple method for the detection of thiram. In the range of 0–7.5 μM, the absorbance intensity was linearly related to the concentration of thiram, and the detection limit was 0.0845 μM. The F–Cu nanozyme was successfully applied to the colorimetric detection of thiram in real samples. [ABSTRACT FROM AUTHOR]

Hydrothermally synthesized manganese dioxide (MnO2) has attracted significant attention in supercapacitor applications due to its exceptional electrochemical properties. This research systematically explores the influence of hydrothermal temperatures of 105 °C (M1), 120 °C (M2), and 150 °C (M3) on the structural and electrochemical characteristics of MnO2-based supercapacitors. From field effect scanning electron microscopy (FESEM) images, the average diameter of MnO2 nanorods is 139 ± 3 nm, 140 ± 5 nm, and 156 ± 3 nm for M1, M2, and M3. The crystalline quality of MnO2 increases by increasing the hydrothermal temperature (M3 sample). Shifting the Raman peak from 637 to 654 cm−1 is observed due to the enhancement in crystallinity and nanorod size in the M3 sample. Higher surface area for smaller nanorods (M1) is also confirmed by the BET (Brunauer–Emmett–Teller) technique. At the scan rate of 10 mV/s, the specific capacitance obtained is 142 (M1), 135 (M2), and 131 (M3) F/g. By elucidating the intricate relationship between hydrothermal temperature and the resultant MnO2 properties, this study provides valuable insights for optimizing the synthesis conditions to enhance the performance of MnO2-based supercapacitors. [ABSTRACT FROM AUTHOR]

The surface area of the working electrode plays a crucial role in determining the sensor's performance, especially in enzymatic sensors. Increasing the surface area of the working electrode has a significant impact on the sensor's functionality. This research focused on developing textile-based sensors using a multi-layer concept, employing the direct coating method. Two different sensors which are multilayer textile-based sensor (MTBS) and single-layer textile-based sensor (STBS) were prepared, while commercial screen-printed carbon electrode (SPCE) was also used as a comparison. The measurements were carried out using potassium ferricyanide solutions with concentrations of 0.01 M, 0.02 M, 0.03 M, 0.04 M, and 0.05 M at a voltage of 1 V, with a maximum duration up to the end of the measurement and a time interval of 0.5 s. According to the research findings, the fluid spreading speed of the SPCE is the lowest when compared to the spreading speeds of the MTBS and STBS. Specifically, the fluid spreading speed of the SPCE is 4.3 times slower than that of the STBS and 51 times slower than that of the MTBS. Utilizing a multi-layer concept with specific coatings can lead to better-performing sensors in terms of stability and sensitivity. The MTBS exhibits the greatest sensitivity, as indicated by its linear equation slope of 717.230 µA µM−1 cm−2. [ABSTRACT FROM AUTHOR]

Graphene fibers (GFs), assembled from graphene-based building blocks, have received considerable attention both from academia and industry due to their intriguing features of high specific surface area, lightweight, easy functionalization, excellent mechanical, electrical and thermal properties. Herein, we have summarized current research status of GFs in terms of their latest fabrication techniques, characterization methods and reduction processes. Wet and dry spinning, dimension-confined hydrothermal strategy, electrophoretic self-assembly, and film conversion fabrication techniques are mainly discussed to optimize the best fabrication conditions. Moreover, various characterization techniques and reduction processes of GFs are also elaborated in detail. Finally, a perspective of the future development and applications of GFs have been given a separate portion in this review. [ABSTRACT FROM AUTHOR]

Hospital surfaces are known to contribute to the spread of healthcare-associated antimicrobial pathogens. Environmental sampling can help locate reservoirs and determine intervention strategies, although sampling and detection can be labor intensive. Composite approaches may help reduce time and costs associated with sampling and detection. We investigated optimum surface areas for sampling antimicrobial-resistant organisms (AROs) with a single side of cellulose sponge, created theoretical composites (TC) by adding recovery results from multiple optimum areas, then compared the TC to the standard Centers for Disease Control and Prevention sampling method (one sponge using all sides, whole tool; (WT)). Five AROs were evaluated: carbapenemase-producing KPC+ Klebsiella pneumoniae (KPC), Acinetobacter baumannii (AB), methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecalis (VRE) and Clostridioides difficile spores (CD). Steel coupons comprising four surface areas (323; 645; 1,290 and 2,258 cm2) were inoculated, dried, and sampled with one sampling pass using the larger side (face) or the smaller side (edge) of a pre-moistened cellulose sponge tool. Based on the optimum areas determined for each organism, composite areas were 1,290 cm2 for MRSA and VRE, 1,936 cm2 for AB, 2,580 cm2 for CD spores and 3,870 cm2 for KPC. Total colony forming units (CFU) recovered using a composite approach was greater or comparable than using multiple WT samplings (over the same area as the composite) for MRSA, VRE and AB (130%; 144% and 95%) yet less than if using multiple WT samplings for KP and CD (47% and 66%). We propose a conservative composite sampling strategy if the target organism is unknown; 323 cm2 sampling area for each of the four sides of the sponge, (1290 cm2 total). The conservative composite sampling strategy improved the recovery of KP (from 47% to 85% of multiple WT samplings), while MRSA, VRE, AB and CD (131%; 144%; 97% and 66%) remained within 5% to that of the optimum area TC. [ABSTRACT FROM AUTHOR]

Developing porous materials with ultrahigh surface areas for gas storage (for example, methane) is attractive but challenging. Here, we report two isostructural three-dimensional covalent organic frameworks (COFs) with a rare self-catenated alb-3,6-Ccc2 topology and a pore size of 1.1 nanometer. Notably, these imine-linked microporous COFs show both high gravimetric Brunauer–Emmett–Teller (BET) surface areas (~4400 square meters per gram) and volumetric BET surface areas (~1900 square meters per cubic centimeter). Moreover, their volumetric methane uptake reaches up to 264 cubic centimeter (standard temperature and pressure) per cubic centimeter [cm3 (STP) cm−3] at 100 bar and 298 kelvin, and they exhibit the highest volumetric working capacity of 237 cm3 (STP) cm−3 at 5 to 100 bar and 298 kelvin among all reported porous crystalline materials. [ABSTRACT FROM AUTHOR]

ABSTRACT Objectives Study Design Settings Participants Main Outcome Measures Results Conclusions We aimed to assess the outcomes of fat graft myringoplasty augmented with hyaluronic acid in closing large‐sized eardrum perforations compared to the traditional underlay cartilage‐perichondrium composite myringoplasty (CPCM).It was a prospective randomised comparative study.It was held in tertiary referral institutions between May 2020 and April 2022.We included 100 patients with a large‐sized eardrum perforation (50%–75% of the eardrum surface area). Using the endoscopic transcanal approach, 50 patients were managed by fat graft myringoplasty augmented with hyaluronic acid, while CPCM managed the other 50 patients.We evaluated the closure rates 1, 6 months and 1 year after surgery. Also, we assessed the audiological performance of the patients with a successful closure before and 1 year after the operation.Fat graft myringoplasty operation was statistically shorter than the CPCM. The closure rate 1 year after surgery was 92% in the first group and 86% in the second group, without a statistically significant difference between both groups. Successful air‐bone gap closure to less than 10 dB occurred in 93.5% of group A and 81.4% of group B without a statistically significant difference. The mean postoperative air‐bone gap was 5.3 ± 3.95 dB in the first group and 7.95 ± 5.17 dB in the second group, with a statistically significant difference.Fat graft myringoplasty augmented with hyaluronic acid was a reliable, safe, simple, and effective manoeuvre to close large‐sized eardrum perforations compared to the conventional CPCM. [ABSTRACT FROM AUTHOR]

Research drives development of sustainable electrocatalytic technologies, but efforts are hindered by inconsistent reporting of advances in catalytic performance. Iridium-based oxide catalysts are widely studied for electrocatalytic technologies, particularly for the oxygen evolution reaction (OER) for proton exchange membrane water electrolysis, but insufficient techniques for quantifying electrochemically accessible iridium active sites impede accurate assessment of intrinsic activity improvements. We develop mercury underpotential deposition and stripping as a reversible electrochemical adsorption process to robustly quantify iridium sites and consistently normalize OER performance of benchmark IrOx electrodes to a single intrinsic activity curve, where other commonly used normalization methods cannot. Through rigorous deconvolution of mercury redox and reproportionation reactions, we extract net monolayer deposition and stripping of mercury on iridium sites throughout testing using a rotating ring disk electrode. This technique is a transformative method to standardize OER performance across a wide range of iridium-based materials and quantify electrochemical iridium active sites. [ABSTRACT FROM AUTHOR]

Many oil reservoirs face production decline, so using enhanced oil recovery methods and well stimulation techniques to increase well productivity has been beneficial and essential. Acid injection into the rock matrix is one of the best stimulation methods to improve oil production. The type of acid used in acid injection operations varies based on reservoir conditions, such as temperature, lithology, and acid‐rock contact time. Reservoir heterogeneity, such as the density and orientation of fractures, affects the performance of acidizing operations. Fracture orientation affects the hydraulic conductivity of post‐acid formation in the near‐wellbore area. In this study, the effect of fracture orientation on acid flow in porous media was visually observed using a transparent cell (micromodel). Image processing techniques were employed to study acid distribution in the carbonate‐fractured rock sample. The results showed that the effectiveness of acid treatment is higher in intersecting fractures compared to parallel fractures, and in parallel fractures compared to fractures perpendicular to the flow direction. At the end of the acid injection, the cumulative dimensionless index (DI), defined as the ratio of the aperture surface area to the surface area in contact with the acid, was 0.57, 0.38, and −0.11 for the crossed, parallel, and vertical fractures, respectively. The aperture surface area refers to the total area of the openings within the fracture network, while the surface area in contact with the acid denotes the portion of the fracture surface directly exposed to the acid during the acidizing process. This introduced index quantitatively measures acidizing effectiveness in widening fracture networks in carbonate reservoirs providing insight into alterations in fracture size and permeability due to acid treatment. After three stages of acid injection, the DI for the fracture aperture in the parallel section of intersecting fractures is 33.3% higher than that for the fracture aperture in the parallel fracture. Considering the additional fracture aperture in the vertical sections of the intersecting fractures, compared to parallel fractures, the superior effectiveness of intersecting fractures becomes more evident. Nevertheless, vertical fractures demonstrated minimal and sometimes negative impact. Fracture orientation impacts acidizing operations, guiding strategies for better production, recovery rates, and reservoir characterization in the oil industry. [ABSTRACT FROM AUTHOR]

Summary Leaf architecture impacts the ease of gases diffusion, biochemical process, and photosynthetic performance. For balsam poplar, a widespread North American species, the influence of water availability on leaf anatomy and subsequent photosynthetic performance remains unknown. To address this shortcoming, we characterized the anatomical changes across the leaf profile in three‐dimensional space for saplings subjected to soil drying and rewatering using X‐ray microcomputed tomography. Our hypothesis was that higher abundance of bundle sheet extensions (BSE) minimizes drought‐induced changes in intercellular airspace volume relative to mesophyll volume (i.e. mesophyll porosity, θIAS) and aids recovery by supporting leaf structural integrity. Leaves of ‘Carnduff‐9’ with less abundant BSEs exhibited greater θIAS, higher spongy mesophyll surface area, reduced palisade mesophyll surface area, and less veins compared with ‘Gillam‐5’. Under drought conditions, Carnduff‐9 showed significant changes in θIAS across leaf profile while that was little for ‘Gillam‐5’. Under rewatered conditions, drought‐induced changes in θIAS were fully reversible in ‘Gillam‐5’ but not in ‘Carnduff‐9’. Our data suggest that a ‘robust’ leaf structure with higher abundance of BSEs, reduced θIAS, and relatively large mesophyll surface area provides for improved photosynthetic capacity under drought and supports recovery in leaf architecture after rewatering in balsam poplar. [ABSTRACT FROM AUTHOR]

In the context of global warming, the dry reforming of methane (DRM) has gained significant attention due to its ability to simultaneously deplete two greenhouse gases, i. e. CH4 and CO2, and generate syngas. Herein, strontium‐promoted Lanthanum‐zirconia supported Ni catalysts are investigated for DRM and characterized by X‐ray diffraction, surface area and porosity, FTIR‐RAMAN spectroscopy, and temperature‐programmed experiments. The Ni/LaZr catalyst contains formate and oxycarbonate‐like CO2‐interacting species, while strontium‐promoted catalysts have additional ionic CO32− species. The current catalyst system of 2 % strontium‐promoted Ni/LaZr has active sites derived from three types of NiO: easily reducible, moderately interacted, and strongly interacted. During the DRM reaction over the current system, CO2 is a better oxidant than O2 for removing carbon deposits. Additionally, the catalysts attain higher reducibility under oxidizing gas (CO2) and reducing gas (H2) during the DRM reaction. For optimal hydrogen yield of approximately 60 % within 420 minutes of operation over Ni2Sr/LaZr catalyst, a balance between the population of active site Ni and CO2‐interacting surface species is necessary. [ABSTRACT FROM AUTHOR]

In this study, a novel electrochemiluminescent (ECL) sensor for highly sensitive detection of trilobatin (Tri) was developed based on silver metal–organic frameworks (AgMOFs) and nitrogen-doped carbon quantum dots (N-CDs). N-CDs exhibited high ECL intensity but poor ECL stability, while AgMOFs had a large specific surface area, high porosity, and good adsorption properties. Compositing both of them not only improved the ECL stability of N-CDs, but also enhanced the ECL strength of materials, so AgMOF@N-CD composites were used as the luminophore of the sensor. Under the optimized conditions, the ECL sensor showed a linear range of 1.0 × 10−7 M to 1.0 × 10−3 M for the detection of Tri, and the detection limit was as low as 5.99 × 10−8 M (S/N = 3). In addition, the sensor had excellent reproducibility, stability, and anti-interference ability. It could be utilized for the detection of Tri in real samples with recoveries of 95.78–102.26%, indicating that the constructed ECL sensor for detecting Tri possessed better application prospects. [ABSTRACT FROM AUTHOR]

A high-efficiency biosorbent based on the low-priced jute fiber was developed, characterized, and applied to remove the emerging organic contaminant diclofenac from aqueous solutions. Jute fiber was treated by NaOH (named AJF) followed by grafting different amounts of trimethyl[3-(trimethoxysilyl) propyl] ammonium chloride (named AJF-TTSAC). The composition, morphology, porosity, and adsorption features of the neat and modified jute fiber were evaluated and compared. The surface of neat JF was smooth, nonporous, and free of cracks. NaOH treatment increased the fibrillation, created cracks and grooves, and increased the oxygen content, total pore volume, and surface area. In comparison to AJF, grafting TTSAC filled in the crevices, grooves, and spaces between fibrillates, and decreased the total pore volume and surface area. The adsorption of diclofenac by the neat and modified JF occurred at highly acidic pHo and peaked at pHo 3. Among the neat and modified JF, AJF-TTSAC5 was the most efficient followed by AJF. The efficiency of AJF and AJF-TTSAC5 was highest using 1.00 g/L, at 35 °C and was not affected by the presence of NaCl. The Elovich, pseudo-first-order, and pseudo-second-order models described the adsorption kinetic satisfactorily with the marginal advantage of Elovich for AJF and pseudo-second-order for AJF-TTSAC5. The isotherm study exposed the multilayer and physisorption nature of the adsorption of diclofenac onto AJF and AJF-TTSAC5. The Langmuir monolayer saturation capacity of AJF-TTSAC5 was 37.43 mg/g which revealed its great potential relative to other adsorbents in the literature. The AJF and AJF-TTSAC5 were easily regenerated using distilled water and kept good performance for 5 repetitive cycles. [ABSTRACT FROM AUTHOR]

Electro‐ionic artificial muscles, consisting of a configuration where an electrolyte membrane is flanked by two active electrodes, have emerged as transformative components in the field of soft robotics. Despite this, the current actuation performance falls short for many practical applications, because most existing electrode materials exhibit limitations in terms of their properties. Here, a multifunctional active electrode material is reported for an electro‐ionic artificial muscle, employing a triazine framework that incorporates 6,6′‐Dicyano‐2,2′‐bipyridyl (DCB‐TF). The multifunctional DCB‐TF boasts fully conjugated bonds, facilitating fast electron transfer, high porosity for ion accommodation, a substantial surface area of 1800 m2 g−1 for charge storage, numerous active sites for ion interactions, and complete aromatic rings contributing to stability. The application of DCB‐TF to the active electrodes in the electro‐ionic artificial muscles yields remarkable actuation performance, including a substantial bending displacement of 24 mm at 0.5 V and 0.2 Hz, a rapid response time of 2 s, and outstanding durability sustained over 3.4 million continuous cycles. Consequently, these soft actuators have enabled a dragonfly demonstration as a form of kinetic art. [ABSTRACT FROM AUTHOR]

The separators used in lithium‐sulfur (Li–S) batteries play a crucial role in their cycling performance and safety. Current commercial separators lack the ability to efficiently regulate polysulfide shuttling and are prone to thermal runaway at high temperatures. Recent studies have shown that multifunctional separators can boost the electrochemical performance and safety of Li–S batteries. Metal–organic frameworks (MOFs) have emerged as promising materials for modifying separators due to their large specific surface areas and highly ordered tunable nanopores. Herein, this review focuses on the advancements in developing MOFs, their derivatives, and MOFs‐based composites as separator coatings to address the shortcomings of Li–S batteries. The mechanisms behind these modified separators, designed to inhibit lithium polysulfide shuttling and lithium dendrite growth, are discussed, emphasizing the relationship between the structure and electrochemical performance. The impact of these modified separator coatings on battery safety is also explored, aiming to design suitable composite films for high‐safety Li–S batteries. Furthermore, future perspectives are outlined to guide practical applications and overcome the remaining challenges associated with MOFs‐modified separators. [ABSTRACT FROM AUTHOR]

While it is likely that ecological context is important, the factors that facilitate and maintain variable levels of intraspecific diversity in Salmonidae fishes across environments remain unclear. Using a meta‐analysis of sympatric ecotype assemblages from two salmonid genera—Salvelinus and Coregonus—we evaluated the importance of ecological factors determining the number of sympatric ecotypes (i.e. 2–7) and the level of trait divergence between them. We found that ecotype diversity increased with lake depth and surface area in both Coregonus and Salvelinus. Further, diversity in Coregonus increased with latitude, while the number of ecotypes in Salvelinus assemblages was linked to climatic seasonality. In comparing the two genera, we found elevated divergence in traits related to ontogeny (i.e. age and body shape) in Salvelinus and gill raker count in Coregonus. Trait divergence in life history traits (i.e. age and body length) in Salvelinus increased with seasonality, whereas contrasting relationships of latitude to body length and gill rakers were found in Coregonus. We also found similar levels of divergence in trait variance in the two genera, suggesting that among‐ecotype differences in phenotypic variability are not more common in one genus than the other. Overall, ecosystem characteristics, including lake location, climate and morphometry, are clearly important for where these genera have diversified, but the variables that are most closely associated with intraspecific diversity differ between the two genera studied and depend on whether diversity is quantified using number of ecotypes or trait divergence. [ABSTRACT FROM AUTHOR]

Prussian blue analogues (PBAs) have been widely studied in aqueous zinc‐ion batteries (AZIBs) due to the characteristics of large specific surface area, open aperture, and straightforward synthesis. In this work, vanadium‐based PBA nanocubes were firstly prepared using a mild in situ conversion strategy at room temperature without the protection of noble gas. Benefiting from the multiple‐redox active sites of V3+/V4+, V4+/V5+, and Fe2+/Fe3+, the cathode exhibited an excellent discharge specific capacity of 200 mAh g−1 in AZIBs, which is much higher than those of other metal‐based PBAs nanocubes. To further improve the long‐term cycling stability of the V‐PBA cathode, a high concentration water‐in‐salt electrolyte (4.5 M ZnSO4+3 M Zn(OTf)2), and a water‐based eutectic electrolyte (5.55 M glucose+3 M Zn(OTf)2) were designed to successfully inhibit the dissolution of vanadium and improve the deposition of Zn2+ onto the zinc anode. More importantly, the assembled AZIBs maintained 55 % of their highest discharge specific capacity even after 10000 cycles at 10 A g−1 with superior rate capability. This study provides a new strategy for the preparation of pure PBA nanostructures and a new direction for enhancing the long‐term cycling stability of PBA‐based AZIBs at high current densities for industrialization prospects. [ABSTRACT FROM AUTHOR]

One of the most significant steps for the widespread application of Proton Exchange Membrane Fuel Cells (PEMFC) is the development of an efficient and corrosion-resistant electrocatalyst for Hydrogen Oxidation Reaction (HOR). To achieve an enhanced electrocatalytic activity towards HOR, we developed a carbon-free electrocatalyst that performs on par with the Pt/C commercial-based catalyst. Pt nanoparticles dispersed on hydrogenated WO 3 surfaces were synthesized and experimentally shown to be an efficient HOR electrocatalyst. Furthermore, different characterizations and electrochemical studies validate the performances of all the hydrogenated samples. Pt/a-WO 3 /H400, hydrogenated at 400 °C, exhibits excellent electrocatalytic activity in terms of onset potential, limiting current density, and electrochemical surface area (ECSA). The membrane electrode assembly (MEA) was fabricated, and its single-cell performance was carried out using Pt/a-WO 3 /H300, Pt/a-WO 3 /H400, and Pt/a-WO 3 /H500 at the anode with Pt loading of 0.125 mg/cm2. The single-cell performance of Pt/a-WO 3 /H400 as anode electrocatalyst has the highest power density (540 mW/cm2) at 50 °C and high durability, compared to Pt/C. The enhanced electrocatalytic performance is attributed to the synergistic catalytic effect between Pt nanoparticles and the WO 3-x interface. This occurs due to the preferential orientation of the highly active (002) facet and the creation of an optimum amount of oxygen vacancies due to the hydrogenation impact. • a-WO 3 hydrogenated at different temperatures (300 °C, 400 °C, 500 °C) synthesized. • Pt/a-WO 3 /H400, hydrogenated at 400 °C, have the highest electrocatalytic activity. • Pt/a-WO 3 /H400 shows maximum power density 540 mWcm−2 at Pt loading 0.125 mgcm−2. • Presence of optimum oxygen vacancies in the a-WO 3 /H400 hydrogenated surface. • Robust SMSI interaction between Pt and a-WO 3 /H400 interface observed. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, zinc silicate hybrid scaffolds with hierarchical meso/macroporous structures were synthesized using evaporation-induced self-assembly and sacrificial foamy templates. F127 triblock copolymer and polyurethane (PU) foam served as templates for mesoporosity and macroporosity, respectively. The scaffolds were calcined at 550, 650, and 750 °C for 2 h to remove the templates and form the crystalline phase. Analytical techniques, including BET, XRD, SEM, FTIR, and STA, were used to study the impact of calcination temperature on the scaffolds' meso-texture and crystalline phase. Results showed that increasing the calcination temperature to 750 °C significantly enhanced the overall crystallinity. The crystallized ZnO content increased from 10.3 wt% to 32 wt%, and the willemite (Zn 2 SiO 4) crystalline phase formed. Willemite content was approximately 3 wt% at 650 °C and 67 wt% at 750 °C, as determined by quantitative XRD analyses via Rietveld refinement. The emergence of the willemite phase adversely impacted the specific surface area, leading to a reduction from 123.18 m2/g to 2.18 m2/g, and compromised meso-texture-related characteristics, indicating a substantial disruption in mesoporosity. The pure willemite sample was also obtained by increasing the calcination temperature up to 1000 °C. Although the sample contained no secondary phase, the specific surface area and total mesopore volume were drastically reduced, indicating the negative effect of high calcination temperature on mesoporosity. In contrast to the mesostructure, the macrostructure of the scaffolds exhibited negligible sensitivity to calcination temperature, maintaining a mean macropore diameter of around 200 μm. Furthermore, the in vitro performance of the scaffolds was evaluated by assessing apatite formation ability, degradability, and cytocompatibility. It was demonstrated that the scaffolds calcined at 750 °C exhibited superior performance in terms of apatite formation and cytocompatibility when cultivated with MG-63 human osteosarcoma cells. [ABSTRACT FROM AUTHOR]

Atom-thin SnO 2 (a-SnO 2) shows promising potential for applications in gas sensors. However, its high working temperature can cause agglomeration, leading to a decrease in the specific surface area and resulting in performance deterioration of the sensors. In this study, g-C 3 N 4 was utilized as a thermal support to address this issue and improve the gas-sensing properties of a-SnO 2. When a-SnO 2 was grown with 10 wt% g-C 3 N 4 dispersed evenly in ethylenediamine, the gas-sensing performance of the composite improved significantly, including the response value (R a / R g = 8.8–10 ppm HCHO), fast response (τ res = 1.6 s), ultralow detection limit (0.1 ppm), long-term stability and humidity-resistance properties. This work not only introduces a method to utilize a thermal support for atom-thin metal oxides, enhancing their stability at high working temperatures but also investigates the underlying mechanism. This study provides valuable insights into the application of ultrathin metal oxides. Additionally, it facilitates the development of a portable smart system for detecting HCHO contamination in practical settings. [ABSTRACT FROM AUTHOR]

The amount of As(III) adsorbed and the interfacial process are closely associated with the phase transformation of Schwertmannite (SCH). At present, studies on the adsorption characteristics of As(III) on SCH and the accompanying phase transformation process, especially the related mechanisms under the mediation of iron-reducing bacteria (FeRB) and sulfate-reducing bacteria (SRB), are limited in existing literature. With the help of continuous characterization, the adsorption behavior of As(III) on SCH was explored, as well as the transformation processes of SCH during these processes. The findings revealed that the SCH, synthesized by the KMnO4 oxidation and ethanol modification methods, exhibited excellent physical adsorption capacity for As(III) due to their increasing specific surface area and porosity. At room temperature (20°C), the saturation adsorption capacities of As(III) by M-SCH and Y-SCH reached 62.69 and 58.62 mg/g, respectively. Moreover, the generation and phase transformation of As(III)-bearing ferrihydrite were observed within a 60-min timeframe. It is the first time this phenomenon has been observed in such a short time, which is presumed to be an intermediate stage in the transformation of SCH into goethite. Furthermore, both FeRB and SRB could enhance the adsorption capacity of SCH for As(III). Comparatively, SRB has a more substantial impact on SCH's phase transformation. These insights are valuable for the practical application of SCH in treating As(III) pollution. [ABSTRACT FROM AUTHOR]

Carbon nanofillers in general and graphene in particular are considered as promising potential candidates in catalysis due to their two‐dimensional (2D) nature, zero bandwidth, single atom thickness with a promising high surface area: volume ratio. Additionally, graphene oxide via result of tunable electrical properties has also been developed as a catalytic support for metal and metal oxide nanofillers. Moreover, the possession of higher chemical stability followed by ultrahigh thermal conductivity plays a prominent role in promoting higher reinforcement of catalytically active sites. In this review we have started with an overview of carbon nanofillers as catalyst support, their main characteristics and applications for their use in heterogeneous catalysis. The review article also critically focusses on the catalytic properties originating from both functional groups as well as doping. An in‐depth literature on the various reaction catalysed by metal oxide based nanoparticles supported on GO/rGO has also been incorporated with a special focus on the overall catalytic efficiency with respect to graphene contribution. The future research prospective in the aforementioned field has also been discussed. [ABSTRACT FROM AUTHOR]